SVM124-A
July, 1996
INVERTEC V250-S
For use with machine Code Numbers 10102 to 10188
Safety Depends on You
Lincoln arc welding and cutting
equipment is designed and built
with safety in mind. However, your
overall safety can be increased by
proper installation ... and thought-
ful operation on your part. DO
NOT INSTALL, OPERATE OR
REPAIR THIS EQUIPMENT
WITHOUT READING THIS
MANUAL AND THE SAFETY
PRECAUTIONS CONTAINED
THROUGHOUT. And, most
importantly, think before you act
and be careful.
SERVICE MANUAL
World's Leader in Welding and Cutting Products
Premier Manufacturer of Industrial Motors
Sales and Service through Subsidiaries and Distributors Worldwide
22801 St. Clair Ave. Cleveland, Ohio 44117-1199 U.S.A. Tel. (216) 481-8100
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ii
ii
SAFETY
ARC RAYS can burn.
ELECTRIC SHOCK can
4.a. Use a shield with the proper filter and cover
plates to protect your eyes from sparks and
the rays of the arc when welding or observing
open arc welding. Headshield and filter lens
should conform to ANSI Z87. I standards.
kill.
3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.
Do not touch these “hot” parts with your bare
skin or wet clothing. Wear dry, hole-free
gloves to insulate hands.
4.b. Use suitable clothing made from durable flame-resistant
material to protect your skin and that of your helpers from
the arc rays.
3.b. Insulate yourself from work and ground using dry insulation.
Make certain the insulation is large enough to cover your full
area of physical contact with work and ground.
4.c. Protect other nearby personnel with suitable, non-flammable
screening and/or warn them not to watch the arc nor expose
themselves to the arc rays or to hot spatter or metal.
In addition to the normal safety precautions, if welding
must be performed under electrically hazardous
conditions (in damp locations or while wearing wet
clothing; on metal structures such as floors, gratings or
scaffolds; when in cramped positions such as sitting,
kneeling or lying, if there is a high risk of unavoidable or
accidental contact with the workpiece or ground) use
the following equipment:
FUMES AND GASES
can be dangerous.
5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing these
• Semiautomatic DC Constant Voltage (Wire) Welder.
• DC Manual (Stick) Welder.
fumes and gases.When welding, keep
your head out of the fume. Use enough
• AC Welder with Reduced Voltage Control.
ventilation and/or exhaust at the arc to keep
fumes and gases away from the breathing zone. When
welding with electrodes which require special
ventilation such as stainless or hard facing (see
instructions on container or MSDS) or on lead or
cadmium plated steel and other metals or coatings
which produce highly toxic fumes, keep exposure as
low as possible and below Threshold Limit Values (TLV)
using local exhaust or mechanical ventilation. In
confined spaces or in some circumstances, outdoors, a
respirator may be required. Additional precautions are
also required when welding on galvanized steel.
3.c. In semiautomatic or automatic wire welding, the electrode,
electrode reel, welding head, nozzle or semiautomatic
welding gun are also electrically “hot”.
3.d. Always be sure the work cable makes a good electrical
connection with the metal being welded. The connection
should be as close as possible to the area being welded.
3.e. Ground the work or metal to be welded to a good electrical
(earth) ground.
5.b. Do not weld in locations near chlorinated hydrocarbon vapors
coming from degreasing, cleaning or spraying operations.
The heat and rays of the arc can react with solvent vapors to
form phosgene, a highly toxic gas, and other irritating
products.
3.f. Maintain the electrode holder, work clamp, welding cable and
welding machine in good, safe operating condition. Replace
damaged insulation.
3.g. Never dip the electrode in water for cooling.
5.c. Shielding gases used for arc welding can displace air and
cause injury or death. Always use enough ventilation,
especially in confined areas, to insure breathing air is safe.
3.h. Never simultaneously touch electrically “hot” parts of
electrode holders connected to two welders because voltage
between the two can be the total of the open circuit voltage
of both welders.
5.d. Read and understand the manufacturer’s instructions for this
equipment and the consumables to be used, including the
material safety data sheet (MSDS) and follow your
employer’s safety practices. MSDS forms are available from
your welding distributor or from the manufacturer.
3.i. When working above floor level, use a safety belt to protect
yourself from a fall should you get a shock.
3.j. Also see Items 6.c. and 8.
5.e. Also see item 1.b.
Mar ‘95
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SAFETY
WELDING SPARKS can
cause fire or explosion.
CYLINDER may explode
if damaged.
6.a. Remove fire hazards from the welding area.
If this is not possible, cover them to prevent
7.a. Use only compressed gas cylinders
containing the correct shielding gas for the
the welding sparks from starting a fire.
Remember that welding sparks and hot
materials from welding can easily go through small cracks
and openings to adjacent areas. Avoid welding near
hydraulic lines. Have a fire extinguisher readily available.
process used and properly operating
regulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable for
the application and maintained in good condition.
7.b. Always keep cylinders in an upright position securely
chained to an undercarriage or fixed support.
6.b. Where compressed gases are to be used at the job site,
special precautions should be used to prevent hazardous
situations. Refer to “Safety in Welding and Cutting” (ANSI
Standard Z49.1) and the operating information for the
equipment being used.
7.c. Cylinders should be located:
•Away from areas where they may be struck or subjected to
physical damage.
6.c. When not welding, make certain no part of the electrode
circuit is touching the work or ground. Accidental contact
can cause overheating and create a fire hazard.
•A safe distance from arc welding or cutting operations and
any other source of heat, sparks, or flame.
7.d. Never allow the electrode, electrode holder or any other
electrically “hot” parts to touch a cylinder.
6.d. Do not heat, cut or weld tanks, drums or containers until the
proper steps have been taken to insure that such procedures
will not cause flammable or toxic vapors from substances
inside. They can cause an explosion even though they have
been “cleaned”. For information, purchase “Recommended
Safe Practices for the Preparation for Welding and Cutting of
Containers and Piping That Have Held Hazardous
Substances”, AWS F4.1 from the American Welding Society
(see address above).
7.e. Keep your head and face away from the cylinder valve outlet
when opening the cylinder valve.
7.f. Valve protection caps should always be in place and hand
tight except when the cylinder is in use or connected for
use.
7.g. Read and follow the instructions on compressed gas
cylinders, associated equipment, and CGA publication P-l,
“Precautions for Safe Handling of Compressed Gases in
Cylinders,” available from the Compressed Gas Association
1235 Jefferson Davis Highway, Arlington, VA 22202.
6.e. Vent hollow castings or containers before heating, cutting or
welding. They may explode.
6.f. Sparks and spatter are thrown from the welding arc. Wear oil
free protective garments such as leather gloves, heavy shirt,
cuffless trousers, high shoes and a cap over your hair. Wear
ear plugs when welding out of position or in confined places.
Always wear safety glasses with side shields when in a
welding area.
FOR ELECTRICALLY
powered equipment.
6.g. Connect the work cable to the work as close to the welding
area as practical. Work cables connected to the building
framework or other locations away from the welding area
increase the possibility of the welding current passing
through lifting chains, crane cables or other alternate cir-
cuits. This can create fire hazards or overheat lifting chains
or cables until they fail.
8.a. Turn off input power using the disconnect
switch at the fuse box before working on
the equipment.
8.b. Install equipment in accordance with the U.S. National
Electrical Code, all local codes and the manufacturer’s
recommendations.
6.h. Also see item 1.c.
8.c. Ground the equipment in accordance with the U.S. National
Electrical Code and the manufacturer’s recommendations.
Mar ‘95
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SAFETY
5. Toujours porter des lunettes de sécurité dans la zone de
PRÉCAUTIONS DE SÛRETÉ
soudage. Utiliser des lunettes avec écrans lateraux dans les
zones où l’on pique le laitier.
Pour votre propre protection lire et observer toutes les instruc-
tions et les précautions de sûreté specifiques qui parraissent
dans ce manuel aussi bien que les précautions de sûreté
générales suivantes:
6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir tout risque d’incendie dû aux étincelles.
7. Quand on ne soude pas, poser la pince à une endroit isolé de
la masse. Un court-circuit accidental peut provoquer un
échauffement et un risque d’incendie.
Sûreté Pour Soudage A L’Arc
1. Protegez-vous contre la secousse électrique:
a. Les circuits à l’électrode et à la piéce sont sous tension
quand la machine à souder est en marche. Eviter toujours
tout contact entre les parties sous tension et la peau nue
ou les vétements mouillés. Porter des gants secs et sans
trous pour isoler les mains.
8. S’assurer que la masse est connectée le plus prés possible
de la zone de travail qu’il est pratique de le faire. Si on place
la masse sur la charpente de la construction ou d’autres
endroits éloignés de la zone de travail, on augmente le risque
de voir passer le courant de soudage par les chaines de lev-
age, câbles de grue, ou autres circuits. Cela peut provoquer
des risques d’incendie ou d’echauffement des chaines et des
câbles jusqu’à ce qu’ils se rompent.
b. Faire trés attention de bien s’isoler de la masse quand on
soude dans des endroits humides, ou sur un plancher
metallique ou des grilles metalliques, principalement dans
les positions assis ou couché pour lesquelles une
grande partie du corps peut être en contact avec la
masse.
9. Assurer une ventilation suffisante dans la zone de soudage.
Ceci est particuliérement important pour le soudage de tôles
galvanisées plombées, ou cadmiées ou tout autre métal qui
produit des fumeés toxiques.
c. Maintenir le porte-électrode, la pince de masse, le câble
de soudage et la machine à souder en bon et sûr état
defonctionnement.
d.Ne jamais plonger le porte-électrode dans l’eau pour le
refroidir.
10. Ne pas souder en présence de vapeurs de chlore provenant
d’opérations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de l’arc peuvent réagir avec les
vapeurs du solvant pour produire du phosgéne (gas forte-
ment toxique) ou autres produits irritants.
e. Ne jamais toucher simultanément les parties sous tension
des porte-électrodes connectés à deux machines à soud-
er parce que la tension entre les deux pinces peut être le
total de la tension à vide des deux machines.
f. Si on utilise la machine à souder comme une source de
courant pour soudage semi-automatique, ces precautions
pour le porte-électrode s’applicuent aussi au pistolet de
soudage.
11. Pour obtenir de plus amples renseignements sur la sûreté,
voir le code “Code for safety in welding and cutting” CSA
Standard W 117.2-1974.
2. Dans le cas de travail au dessus du niveau du sol, se pro-
téger contre les chutes dans le cas ou on recoit un choc. Ne
jamais enrouler le câble-électrode autour de n’importe quelle
partie du corps.
PRÉCAUTIONS DE SÛRETÉ POUR
LES MACHINES À SOUDER À
TRANSFORMATEUR ET À
REDRESSEUR
3. Un coup d’arc peut être plus sévère qu’un coup de soliel,
donc:
a. Utiliser un bon masque avec un verre filtrant approprié
ainsi qu’un verre blanc afin de se protéger les yeux du
rayonnement de l’arc et des projections quand on soude
ou quand on regarde l’arc.
1. Relier à la terre le chassis du poste conformement au code
de l’électricité et aux recommendations du fabricant. Le dis-
positif de montage ou la piece à souder doit être branché à
une bonne mise à la terre.
b. Porter des vêtements convenables afin de protéger la
peau de soudeur et des aides contre le rayonnement de
l‘arc.
c. Protéger l’autre personnel travaillant à proximité au
soudage à l’aide d’écrans appropriés et non-inflamma-
bles.
2. Autant que possible, I’installation et l’entretien du poste
seront effectués par un électricien qualifié.
3. Avant de faires des travaux à l’interieur de poste, la
debrancher à l’interrupteur à la boite de fusibles.
4. Des gouttes de laitier en fusion sont émises de l’arc de
soudage. Se protéger avec des vêtements de protection
libres de l’huile, tels que les gants en cuir, chemise épaisse,
pantalons sans revers, et chaussures montantes.
4. Garder tous les couvercles et dispositifs de sûreté à leur
Mar. ‘93
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vi
MASTER TABLE OF CONTENTS FOR ALL SECTIONS
PAGE
INSTALLATION .......................................................................................................................SECTION A
TECHNICAL SPECIFICATIONS..................................................................................................A-2
SAFETY PRECAUTIONS ............................................................................................................A-3
SELECT SUITABLE LOCATION..................................................................................................A-3
INPUT CONNECTIONS...............................................................................................................A-3
INPUT VOLTAGE RECONNECT PROCEDURE.........................................................................A-4
OUTPUT CONNECTIONS...........................................................................................................A-5
OPERATION
.......................................................................................................................SECTION B
SAFETY INSTRUCTIONS ...........................................................................................................B-2
GENERAL DESCRIPTION...........................................................................................................B-2
CONTROLS AND SETTINGS......................................................................................................B-3
CONSTANT CURRENT PROCESSES........................................................................................B-4
PARALLEL OPERATION.............................................................................................................B-5
OVERLOAD PROTECTION.........................................................................................................B-5
THERMAL PROTECTION............................................................................................................B-5
ACCESSORIES .......................................................................................................................SECTION C
OPTIONS / ACCESSORIES........................................................................................................C-2
CABLE PLUGS......................................................................................................................C-2
REMOTE CONTROLS ..........................................................................................................C-2
MAINTENANCE .......................................................................................................................SECTION D
INPUT FILTER CAPACITOR DISCHARGE PROCEDURE.........................................................D-2
ROUTINE MAINTENANCE..........................................................................................................D-3
FILTER CAPACITOR CONDITIONING ......................................................................................D-3
LOCATION OF MAINTENANCE COMPONENTS.......................................................................D-4
THEORY OF OPERATION .........................................................................................................SECTION E
GENERAL DESCRIPTION...........................................................................................................E-2
INPUT LINE VOLTAGE................................................................................................................E-2
PRE-CHARGE AND PROTECTION ............................................................................................E-3
MAIN TRANSFORMER................................................................................................................E-4
OUTPUT RECTIFICATION AND CONTROL...............................................................................E-5
PROTECTION CIRCUITS............................................................................................................E-6
INSULATED GATE BIPOLAR TRANSISTOR (IGBT) OPERATION............................................E-7
PULSE WIDTH MODULATION (PWM)........................................................................................E-8
TROUBLESHOOTING ................................................................................................................SECTION F
HOW TO USE TROUBLESHOOTING GUIDE ......................................................................F-2
PC BOARD TROUBLESHOOTING PROCEDURES.............................................................F-3
TROUBLESHOOTING GUIDE...............................................................................................F-4
TEST PROCEDURES..........................................................................................................F-11
REPAIR AND REPLACEMENT PROCEDURES.................................................................F-43
RETEST AFTER REPAIR....................................................................................................F-77
ELECTRICAL DIAGRAMS.........................................................................................................SECTION G
PARTS MANUAL ................................................................................................................................P-244
INVERTEC V250-S
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SECTION-A-1
SECTION-A-1
INSTALLATION
TABLE OF CONTENTS
-INSTALLATION SECTION-
TECHNICAL SPECIFICATIONS..................................................................................................A-2
SAFETY PRECAUTIONS ............................................................................................................A-3
SELECT SUITABLE LOCATION..................................................................................................A-3
STACKING.............................................................................................................................A-3
TILTING .................................................................................................................................A-3
HIGH FREQUENCY PRECAUTIONS ...................................................................................A-3
INPUT CONNECTIONS...............................................................................................................A-3
GROUND CONNECTION......................................................................................................A-3
INPUT SUPPLY CONNECTIONS .........................................................................................A-3
POWER INPUT CONNECTION FOR 60HZ MACHINES......................................................A-3
POWER INPUT CONNECTION FOR 50/60 HZ MACHINES................................................A-4
INPUT FUSE AND SUPPLY WIRE .......................................................................................A-4
INPUT VOLTAGE RECONNECT PROCEDURE.........................................................................A-4
OUTPUT CONNECTIONS...........................................................................................................A-5
REMOTE CONTROL RECEPTACLE....................................................................................A-5
OUTPUT CABLES.................................................................................................................A-5
QUICK DISCONNECT PLUGS..............................................................................................A-5
INVERTEC V250-S
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A-2
A-2
INSTALLATION
Technical Specifications - Invertec V250-S
INPUT
THREE PHASE
SINGLE PHASE
Standard
Voltage
Input Current
at Rated Output
34/32/16
Standard
Voltage
Input Current
Model
60Hz
50/60 Hz
at Rated Output
59/57/29
Model
60Hz
50/60 Hz
208/230/460
200/220/400/440
208/230/460 60Hz
200/220/400/440 50/60 Hz
35/33/18/17
58/58/30/30
RATED OUTPUT
THREE PHASE
SINGLE PHASE
Volts at
Amps Rated Amps
Volts at
Duty Cycle(1)
Model
60Hz
60Hz
Duty Cycle(1)
Amps Rated Amps
Model
60Hz
60Hz
†
35% Duty Cycle
60% Duty Cycle
100% Duty Cycle
35% Duty Cycle
60% Duty Cycle
100% Duty Cycle
250
200
165
250
200
165
30
35% Duty Cycle
60% Duty Cycle
100% Duty Cycle
35% Duty Cycle
60% Duty Cycle
100% Duty Cycle
250
200
165
250
200
165
27 -30
28-32
26.5
28-32
26.5
60Hz
60Hz
†
†
28 -30
50/60Hz
50/60Hz
50/60Hz
26 -30
50/60Hz
50/60Hz
50/60Hz
29-32
26.5
28-32
26.5
OUTPUT
THREE PHASE
SINGLE PHASE
Welding
Current Range
1-250 Amps
Constant Open
Circuit Voltage
Welding
Current Range
1-250 Amps
Constant Open
Circuit Voltage
65-80 VDC
65-80 VDC
RECOMMENDED INPUT WIRE AND FUSE SIZES
THREE PHASE SINGLE PHASE
Type 75°C
Copper
Ground
Wire in
Type 75°C
Type 75°C
Copper
Wire in
Type 75°C
Copper
Wire in
Copper
Ground
Wire in
Conduit
Fuse
Input
Fuse
Input
(Superlag) Ampere
(Superlag) Ampere
Input
Voltage
Frequency(2)
or
Breaker
Size
Rating
on
Nameplate
Conduit
Conduit
AWG (IEC) AWG (IEC)
Input
Voltage
Frequency(2)
or
Breaker
Size
Rating
on
Nameplate
Conduit
AWG (IEC) AWG (IEC)
Sizes
Sizes
Sizes
Sizes
208/60
230/60
460/60
50
50
30
34
32
16
10 (6mm2)
10(6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
208/60(3)
230/60(3)
460/60
80
80
40
59
57
29
8 (10mm2)
8 (10mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
200/50/60
220/50/60
400/50/60
440/50/60
50
50
30
30
35
33
18
17
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
200/50/60
220/50/60
400/50/60
440/50/60
80
80
40
40
58
58
30
30
8 (16mm2)
8 (16mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
10 (6mm2)
PHYSICAL DIMENSIONS
Height
Width
Depth
Weight
15.0 in.
9.1 in.
19.7 in.
36 lbs.
381 mm
231 mm
500 mm
17 Kg
(1) Based on a 10 min. period.
(2) Input voltage must be within ±10% of rated value.
(3) For 1 phase use on 208 or 230 VAC input with output usage above 175A/60% or 200A/35%, the #10 input line cord supplied with the unit should be changed to a
#8 or larger conductor cord.
200 & 208VAC input may not meet NEMA/IEC specifications at 250 Amps.
(†)
INVERTEC V250-S
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A-3
A-3
INSTALLATION
Read this entire installation section before you
start installation.
HIGH FREQUENCY PRECAUTIONS
If possible locate the V250-S away from radio con-
trolled machinery. The normal operation of the
V250-S may adversely affect the operation of RF con-
trolled equipment, which may result in bodily injury or
damage to the equipment.
SAFETY PRECAUTIONS
WARNING
INPUT CONNECTIONS
ELECTRIC SHOCK can kill.
• Have an electrician install and ser-
vice this equipment.
The Invertec V250-S should be connected only by a
qualified electrician. Installation should be made in
accordance with all local and national electric codes
and the information detailed below.
• Turn the input power off at the fuse
box before working on equipment.
• Do not touch electrically hot parts.
GROUND CONNECTION
• Be sure to discharge capacitors with
the procedure outlined in the
Maintenance Section of this manual
before working in that area of the
equipment.
Ground per National Electrical Code for 60Hz
machines connect the green lead to earth ground.
For 50/60Hz machines connect the ground terminal
---------------------------------------------------------------------
marked
located in the machine on the lower right
side the base of the welder to earth ground.
SELECT SUITABLE LOCATION
INPUT SUPPLY CONNECTIONS
The Invertec V250-S will operate in harsh environ-
ments. Even so, it is important that simple preventa-
tive measures are followed in order to assure long life
and reliable operation.
Be sure the voltage phase and frequency of the input
power is as specified on the rating plate, located on
the rear of the machine.
• The machine must be located where there is free cir-
culation of clean air such that air movement in the
back and out the front will not be restricted.
Supply line entry provision is in the case rear panel.
POWER INPUT CONNECTION FOR 60HZ
MACHINES
• Dirt and dust that can be drawn into the machine
should be kept to a minimum. Failure to observe
these precautions can result in excessive operating
temperatures and nuisance shutdown.
A 10 ft. power cord is provided and wired into the
machine. Follow the power cord connection instruc-
tions. Incorrect connection may result in equipment
damage.
• Keep machine dry. Shelter from rain and snow. Do
not place on wet ground or in puddles.
Single Phase Input: Connect green lead to ground
per U.S. National Electrical Code. Connect black and
white leads to power. Wrap red lead with tape to pro-
vide 600V insulation.
STACKING
V250-S’s cannot be stacked.
TILTING
Three Phase Input: Connect green lead to ground
per U.S. National Electrical Code. Connect black, red
and white leads to power.
Place the machine directly on a secure, level surface
or on a recommended undercarriage. The machine
may topple over if this procedure is not followed.
INVERTEC V250-S
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A-4
A-4
INSTALLATION
POWER INPUT CONNECTION FOR 50/60 HZ
MACHINES
INPUT VOLTAGE RECONNECT
PROCEDURE
1. Connect terminal marked
per National Electric Code.
2. Connect the supply lines to the line switch. Torque
to 3.0 Nm.
3. Install in accordance with all local and national
electric codes.
to earth ground
When received directly from the factory, units are con-
nected for the highest input voltage, 440 VAC for
50/60 Hz machines and 460 VAC for 60 Hz machines.
If 440 or 460 VAC is the desired input, then the
machine may be connected to the power system with-
out any setup required inside the reconnect door.
However, verify the connection with the following pro-
cedure. For other voltages refer to the instructions
located on the Reconnect Panel Access Door or fol-
low the instructions below.
The Invertec V250-S 50/60 Hz machine is supplied
with one cord connector. The cord connector provides
a strain relief for the input power cord as it passes it
through the rear access hole. The cord connector is
designed for a cord diameter of 7.9 to 27.2mm (.310
to 1.070 in).
CAUTION
Failure to follow these instructions can cause immedi-
ate failure of components within the welder.
------------------------------------------------------------------------
Strip away outer jacket of cord, trim fillers and insert
conductors through cord connector. The jacketed por-
tion of the cord must go through the cord connector.
Tighten both connector screws.
1. Open the access door on the right side of the
machine.
INPUT FUSE AND SUPPLY WIRE
2. For 200-230: Position the large switch to 200-230.
For 380-460: Position the large switch to 380-460.
Refer to the Technical Specifications page at the
beginning of this chapter for the proper fuse sizes and
supply cable sizes.
3. Move the “A” lead to the appropriate terminal.
Refer to figure A.1 below.
• Fuse the input circuit with recommended super lag
fuses or delay type circuit breakers.
• Install the proper fuse in the fuse holder in the main
disconnect panel.
RECONNECT PROCEDURE
.
.
.
Disconnect input power before
inspecting or servicing machine.
1. BE SURE POWER SWITCH IS OFF.
Do not operate with wraparound
removed.
2. CONNECT LEAD 'A' TO DESIRED
INPUT VOLTAGE RANGE.
Do not touch electrically live parts.
440-460V
.
Only qualified persons should install,
use or service this equipment.
380-415V
'A'
220-230V
IF MACHINE CEASES TO OPERATE (NO METER, NO FAN)
AND THERE IS NO OTHER KNOWN FAILURE: CHECK FUSE;
REPLACE WITH SPECIFIED FUSE.
200-208V
3. POSITION SWITCH TO DESIRED INPUT VOLTAGE RANGE.
VOLTAGE=380-460V
VOLTAGE=200-230V
A
THE LINCOLN ELECTRIC CO.
CLEVELAND, OHIO U.S.A.
S21230
Figure A.1 Input Voltage Reconnect Instructions
INVERTEC V250-S
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A-5
A-5
INSTALLATION
QUICK DISCONNECT PLUGS
OUTPUT CONNECTIONS
A quick disconnect system is used for the welding
cable connections. The welding plug included with the
machine is designed to accept a welding cable size of
1/0 to 2/0.
Refer to figure A.2 for the location of the 6 Pin Remote
Receptacle and the Output Terminals.
1. Remove 1 in. (25mm) of welding cable insulation.
SMAW
SOFT
SMAW
CRISP
GTAW
THERMAL
HOT START
5
6
4
7
3
8
9
2
2. Slide rubber boot onto cable end. The boot end
may be trimmed to match the cable diameter.
Soap or other lubricant will help to slide the boot
over the cable.
A
120
85
6 PIN
REMOTE
RECEPTACLE
1
OUTPUT
0
10
170
230
50
15
ARC FORCE
REMOTE
LOCAL
5
6
1
4
7
3
250
8
9
2
1
0
10
BOOT
INVERTEC ¤ V250-S
WELDING CABLE
S
I
-
+
25 mm
TRIM
1 in.
O
OUTPUT TERMINALS
3. Slide the copper tube into the brass plug.
4. Insert cable into copper tube.
FIGURE A.2 OUTPUT CONNECTIONS
5. Tighten set screw to collapse copper tube. Screw
must apply pressure against welding cable. The
top of the set screw will be well below the surface
of the brass plug after tightening.
REMOTE CONTROL RECEPTACLE
Remote control (K857), Arc start switch (K814), Hand
amptrol (K963) and Foot amptrol (K870) connect
directly to 6 pin amphenol on the front of the unit.
SET SCREW
OUTPUT CABLES
Select the output cable size based on Table A.1.
BRASS PLUG
COPPER TUBE
TABLE A.1
Cable Sizes for Combined Length of Electrode and
Work Cable ( Copper Cable Rated at 75°C).
6. Slide rubber boot over brass plug. The rubber
boot must be positioned to completely cover all
electrical surfaces after the plug is locked into the
receptacle.
Length
up to 150 ft.(46m)
up to 250 ft.(72m)
Cable Size
1/0 (50mm2)
2/0 (70mm2)
INVERTEC V250-S
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A-6
A-6
NOTES
INVERTEC V250-S
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SECTION-B-1
SECTION-B-1
OPERATION
TABLE OF CONTENTS
-OPERATION SECTION-
SAFETY INSTRUCTIONS ...........................................................................................................B-2
GENERAL DESCRIPTION...........................................................................................................B-2
OPERATIONAL FEATURES .................................................................................................B-2
WELDING CAPABILITY ........................................................................................................B-2
LIMITATIONS ........................................................................................................................B-2
CONTROLS AND SETTINGS......................................................................................................B-3
CONSTANT CURRENT PROCESSES........................................................................................B-4
MANUAL ARC WELDING (STICK)........................................................................................B-4
AIR CARBON ARC CUTTING...............................................................................................B-4
TIG WELDING .......................................................................................................................B-4
PARALLEL OPERATION.............................................................................................................B-5
OVERLOAD PROTECTION.........................................................................................................B-5
THERMAL PROTECTION............................................................................................................B-5
INVERTEC V250-S
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B-2
B-2
OPERATION
Read and understand this entire section before
operating your machine.
GENERAL DESCRIPTION
The Invertec V250-S is a 250 amp arc welding power
source that utilizes single or three phase input power,
to produce constant current output. The welding
response of this Invertec has been optimized for stick
(SMAW) and TIG (GTAW).
SAFETY INSTRUCTIONS
WARNING
ELECTRIC SHOCK can kill.
OPERATIONAL FEATURES
• Do not touch electrically live parts such
as output terminals or internal wiring.
The Invertec V250-S provides continuous total range
output current adjustment, selectable welding modes
and local or remote output control. Welding character-
istics can be controlled via an arc force control.
Additionally, starting characteristics can be adjusted
via a “hot start” control.
• Insulate yourself from the work and
ground.
• Always wear dry insulating gloves.
____________________________________
WELDING CAPABILITY
FUMES AND GASES
can be dangerous.
The Invertec V250-S is rated at 250 amps, 35% duty
cycle (based on a 10 minute cycle). It is also rated at
165 amps, 100% duty cycle, and 200 amps, 60% duty
cycle.
• Keep your head out of fumes.
• Use ventilation or exhaust to
remove fumes from breathing
zone.
LIMITATIONS
The V250-S is not recommended for pipe thawing.
____________________________________
The V250-S should not be powered from the auxiliary
power supply of an engine welder. Special protection
circuits may operate causing loss of output.
WELDING, CUTTING and
GOUGING SPARKS
can cause fire or explosion
• Keep flammable material away.
• Do not weld, cut or gouge on
containers that have held com-
bustibles.
____________________________________
ARC RAYS
can burn.
• Wear eye, ear and body
protection.
____________________________________
Only qualified personnel should operate this equip-
ment. Observe all safety information throughout this
manual.
INVERTEC V250-S
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B-3
B-3
OPERATION
CONTROLS AND SETTINGS
All operator controls and adjustments are located on the case front of the V250-S. Refer to Figure B.1 and corre-
sponding explanations.
FIGURE B.1 — CASE FRONT CONTROLS.
4
8
SMAW
SOFT
SMAW
CRISP
GTAW
THERMAL
HOT START
5
6
4
7
2
3
8
9
2
A
120
85
5
6
1
OUTPUT
0
10
170
230
3
50
15
ARC FORCE
LOCAL
REMOTE
5
6
1
4
7
3
250
8
9
2
1
0
10
®
INVERTEC V250-S
S
I
+
-
1
O
7
1. Power Switch - Place the lever in the “ON” position
to energize the machine. When the power is on, the
fan will operate and the output will be energized in
SMAW modes. GTAW mode requires remote trig-
ger to energize the output.
4. Mode Switch
GTAW Optimized for touch start use. Triggering at
amphenol is required using an Arc Start Switch,
Amptrol or similar means. Short circuit current is
limited to approximately 25 amps to aid in touch
starting.
2. Output Control - This controls the output current.
Control is provided over the entire output range of
the power source with 1 turn of the control knob.
This control may be adjusted while under load to
change power source output. When using remote
control this function becomes the limit setting.
CC SoftBest for EXX18 thru EXX28 stick elec-
trodes. Output energized when machine is on.
CC Crisp
Use this mode for stick welding with
EXX10 thru EXX14 electrodes. Output energized
when machine is on.
3. Local/Remote Switch - Place in the “LOCAL” posi-
tion to allow output adjustment at the machine.
Place in the “REMOTE” position to allow output
adjustment at remote pot or amptrol. In Remote, the
machine output control pot is the limit setting for
remote control.
5. Hot Start - Controls the amount of starting energy
in SMAW.
INVERTEC V250-S
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B-4
B-4
OPERATION
6. Arc Force - This control functions in SMAW modes
to adjust the Arc Force. The arc is soft at the mini-
mum settings and more forceful or driving at the
maximum settings. Higher spatter levels may be
present at the maximum settings.
CONSTANT CURRENT PROCESSES
MANUAL ARC WELDING (STICK)
The Invertec may be utilized as a manual DC arc
welder with the electrode cable, work cable, and elec-
trode holder being the only equipment required.
RECOMMENDED ARC FORCE/INDUCTANCE
SETTINGS FOR SELECTED APPLICATIONS
AIR CARBON ARC CUTTING
FULL RANGE IS 1-10. 1 is VERY SOFT,
10 IS VERY CRISP
Air carbon arc cutting may be performed with the
Invertec within its output rating using 5/32" (3.9mm)
and 3/16" (4.7mm) diameter carbon rods. Output
cables, an air carbon arc electrode cable assembly,
and a source of compressed air are required.
Nominal
Recommended
Mode
Process Setting
Adjustment Range
CC SMAW 1
(soft)
EXX18 thru
EXX28 stick
5
1 (gentle, may stick) to 9
(forceful, more spatter)
NOTE:
1. Best performance will be at settings of 200 amps
and below.
CC SMAW 2
(crisp)
EXX10 thru
EXX14 stick
6
1
3 to 10
None
Air Carbon Arc
Cutting
2. The electronic protection circuit in the V250S will
limit the current to approximately 290 amps.
7. Output Terminals - These quick disconnect termi-
nals provide connection points for the electrode and
work cables. Refer to Output Connections in the
Installation chapter for proper cable sizes. For
positive polarity welding connect the electrode
cable to the positive terminal and the work cable to
the negative terminal. To weld negative polarity
reverse the electrode and work cables.
TIG WELDING
The V250S is capable of touch start TIG welding. An
electrode cable, work cable, Arc Start Switch or
Amptrol, TIG torch, and gas supply with regulator are
required. Refer to Accessories section of this manual.
Touch starting is done as follows:
8. Thermal Shutdown Indicator - This light will illumi-
nate if an internal thermostat has been activated.
Machine output will return after the internal
components have returned to a normal operating
temperature. See Thermal Protection later in this
chapter.
1. Place the shield cup edge on the work piece.
2. Rock the tungsten down to touch.
3. Trigger the output.
4. Gently rock back the tungsten from the work-
piece.
Note: The short circuit current is limited to 25 amps to
aid in touch starting. Panel output control
becomes the current limit setting when in
remote control
INVERTEC V250-S
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B-5
B-5
OPERATION
PARALLEL OPERATION
The Invertec’s are operable in parallel. For best
results, the currents of each machine should be rea-
sonably well shared. As an example, with two
machines set up in parallel for a 300 amp procedure,
each machine should be set to deliver approximately
150 amps, not 200 amps from one and 100 amps
from the other. This will minimize nuisance feedback
conditions. In general, more than two machines in par-
allel will not be effective due to the voltage require-
ments of procedures in that power range.
To set machine outputs, start with output control pots
and arc force pots in identical positions. Adjust out-
puts and arc forces to maintain current sharing while
establishing the proper output current.
OVERLOAD PROTECTION
The machine is electrically protected from producing
high output currents. Should the output current
exceed 290A, an electronic protection circuit will
reduce the current to less than 200A. The machine
will continue to produce this low current until the pro-
tection circuit is reset. Reset occurs when the output
load is removed.
THERMAL PROTECTION
Thermostats protect the machine from excessive
operating temperatures. Excessive temperatures may
be caused by a lack of cooling air or operating the
machine beyond the duty cycle and output rating. If
excessive operating temperature should occur, the
thermostats will prevent output voltage or current.
Thermostats are self-resetting once the machine cools
sufficiently. If the thermostat shutdown was caused by
excessive output or duty cycle and the fan is operating
normally, the Power Switch may be left on and the
reset should occur within a 15 minute period. If the fan
is not turning or the air intake louvers were obstructed,
then the power must be switched off for 15 minutes in
order to reset. The fan problem or air obstruction must
also be corrected.
INVERTEC V250-S
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B-6
B-6
NOTES
INVERTEC V250-S
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SECTION C-1
SECTION C-1
ACCESSORIES
TABLE OF CONTENTS
-ACCESSORIES SECTION-
OPTIONS / ACCESSORIES........................................................................................................C-2
CABLE PLUGS......................................................................................................................C-2
K852-70 .......................................................................................................................C-2
K852-95 .......................................................................................................................C-2
REMOTE CONTROLS ..........................................................................................................C-2
K857.............................................................................................................................C-2
K963 ............................................................................................................................C-2
K870.............................................................................................................................C-2
K814 ............................................................................................................................C-2
INVERTEC V250-S
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C-2
C-2
ACCESSORIES
OPTIONS / ACCESSORIES
CABLE PLUGS
K852-70 - Cable Plug Kit for 1/0-2/0 cable. Attaches
to welding cable to provide quick disconnect from
machine.
K852-95 - Cable Plug Kit for 2.0-3/0 cable.
NOTE: Two K852-70 plugs are included with the
V250-S.
REMOTE CONTROLS
K857 - Remote Output Control for stick welding.
K963 - Hand Amptroltm for TIG welding. When the
V250-S’s Output Control is in the “Remote” position,
the hand Amptrol energizes the output and controls
the output remotely. The Hand Amptrol connects
directly to the 6 pin Amphenol.
K870 - Foot Amptroltm for TIG welding. When the
V250-S’s Output Control is in the “REMOTE” position,
the foot Amptrol energizes the output and controls the
output remotely. The Hand Amptrol connects directly
to the 6 pin Amphenol.
K814 - Arc Start Switch. Energizes the output for TIG
welding if remote output control of the amperage is
not desired. When using the Arc Start Switch set the
Output Control to the “LOCAL” position.
INVERTEC V250-S
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SECTION D-1
SECTION D-1
MAINTENANCE
TABLE OF CONTENTS
-MAINTENANCE SECTION-
INPUT FILTER CAPACITOR DISCHARGE PROCEDURE.........................................................D-2
ROUTINE MAINTENANCE..........................................................................................................D-3
FILTER CAPACITOR CONDITIONING ......................................................................................D-3
LOCATION OF MAINTENANCE COMPONENTS.......................................................................D-4
INVERTEC V250-S
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D-2
D-2
MAINTENANCE
4. Obtain a high resistance and high wattage resistor
(25-1000 ohms and 25 watts minimum). This resis-
tor is not supplied with machine. NEVER USE A
SHORTING STRAP FOR THIS PROCEDURE.
WARNING
ELECTRIC SHOCK can kill.
• Have an electrician install and service
this equipment.
• Turn the input power off at the fuse
box before working on equipment.
• Do not touch electrically hot parts.
• Prior to Performing preventative main-
tenance, perform the following capaci-
tor discharge procedure to avoid elec-
tric shock.
5. Locate the four capacitor terminals (large hex head
cap screws) shown in Figure D.1. One pair at the
top and one pair at the bottom of the Power Board.
6. Use electrically insulated gloves and insulated pli-
ers. Hold body of the resistor and connect resistor
leads across the two capacitor terminals. Hold
resistor in place for 10 seconds. DO NOT TOUCH
CAPACITOR TERMINALS WITH YOUR BARE
HANDS.
---------------------------------------------------------------------
INPUT FILTER CAPACITOR
DISCHARGE PROCEDURE
1. Turn off input power or disconnect input power
lines.
7. Repeat discharge procedure for the capacitor on
other two terminals.
2. Remove the 5/16" hex head screws from the side
and top of the machine and remove wrap-around
machine cover.
8. Check voltage across terminals of all capacitors
with a DC voltmeter. Polarity of capacitor terminals
is marked on PC board above terminals. Voltage
should be zero. If any voltage remains, repeat this
capacitor discharge procedure.
3. Be careful not to make contact with the capacitor
terminals that are located in the top and bottom of
the Power Board.
FIGURE D.1 — LOCATION OF INPUT FILTER CAPACITOR TERMINALS.
POWER
BOARD
UPPER
CAPACITOR TERMINALS
LOWER
CAPACITOR
TERMINALS
POWER
RESISTOR
INSULATED
PLIERS
RIGHT SIDE OF MACHINE
INSULATED
GLOVES
INVERTEC V250-S
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D-3
D-3
MAINTENANCE
ROUTINE MAINTENANCE
FILTER CAPACITOR
CONDITIONING
1. Perform the following preventive maintenance
procedures at least once every six months. It is
good practice to keep a preventive maintenance
record; a record tag attached to the machine
works best.
A protection circuit is included to monitor the voltage
across filter capacitors C1 and C2. In the event that
the capacitor voltage is too high, the protection circuit
will prevent output. Nominal trip setting is at 230/460
VAC +15%. Reset occurs about 3% lower (230/460
VAC +12%).
2. Remove the machine wrap-around cover and per-
form the input filter capacitor discharge procedure
(detail at the beginning of this chapter).
On new installations, the protection circuit may also
prevent output providing all these circumstances are
met:
3. Keeping the machine clean will result in cooler
operation and higher reliability. Be sure to clean
the following areas with a low pressure air
stream. See figure D.2 for component locations.
1. Machine is connected for 380-415 or 440-460
VAC input.
2. Machine did not have power applied for many
months.
3. Machine will not produce output when power is
first switched on.
•
•
•
•
•
Power and control printed circuit boards
Power switch
Main transformer
If these circumstances apply, the proper action is to
switch the machine on and let it idle for up to 30 min-
utes. This is required to condition the filter capacitors
after an extended storage time. The protection circuit
will automatically reset once the capacitor conditioning
and resultant voltage levels are acceptable. It may be
necessary to turn the power switch off and back on
again after this period.
Input rectifier
Heat sink fins
• Input Filter Capacitors
• Output Terminals
4. Examine capacitors for leakage or oozing. Replace
if needed.
5. Examine the sheet metal case for dents or break-
age. Repair the case as required. Keep the case
in good condition to ensure that high voltage
parts are protected and correct spacings are
maintained. All external sheet metal screws must
be in place to assure case strength and electrical
ground continuity.
6. Check electrical ground continuity. Using an ohm-
meter, measure resistance between either output
terminal and an unpainted surface of the machine
case. (See Figure D.2 for locations.) Meter reading
should be 500,000 ohms or more. If meter reading
is less than 500,000 ohms, check for electrical
components that are not properly insulated from
the case. Correct insulation if needed.
7. Replace machine cover and screws.
INVERTEC V250-S
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D-4
D-4
MAINTENANCE
FIGURE D.2 — LOCATION OF MAINTENANCE COMPONENTS.
INPUT RECTIFIER
CONTROL PC BOARD
POWER PC BOARD
POWER SWITCH
COOLING FANS
OUTPUT TERMINALS
OUTPUT RECTIFIER
HEATSINK FINS
MAIN TRANSFORMER
AUXILIARY TRANSFORMER
INVERTEC V250-S
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E-1
E-1
THEORY OF OPERATION
TABLE OF CONTENTS
-THEORY OF OPERATION SECTION-
GENERAL DESCRIPTION...........................................................................................................E-2
INPUT LINE VOLTAGE................................................................................................................E-2
PRE-CHARGE AND PROTECTION ............................................................................................E-3
MAIN TRANSFORMER................................................................................................................E-4
OUTPUT RECTIFICATION AND CONTROL...............................................................................E-5
PROTECTION CIRCUITS............................................................................................................E-6
INSULATED GATE BIPOLAR TRANSISTOR (IGBT) OPERATION............................................E-7
PULSE WIDTH MODULATION (PWM)........................................................................................E-8
INVERTEC V250-S
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E-2
E-2
THEORY OF OPERATION
GENERAL DESCRIPTION
The Invertec V250-S is a 250 amp arc welding power source that utilizes either single or three phase input power
to produce a constant current output. The output response of this machine has been optimized for the SMAW
and TIG welding processes.
FIGURE E.1 - INPUT VOLTAGE CIRCUITS
MAIN
POWER BOARD
TRANSFORMER
CR1
RELAY
INPUT
RECTIFIER
INPUT
LINE
SWITCH
IGBT
POSITIVE
OUTPUT
TERMINAL
CAPACITOR
R
E
C
O
N
N
E
C
T
IGBT
IGBT
SHUNT
CURRENT
TRANSFORMER
S
W
I
T
C
H
NEGATIVE
OUTPUT
CAPACITOR
F
E
E
D
B
A
C
K
TERMINAL
F
E
E
D
B
A
C
K
IGBT
"A"
L
E
A
D
O
V
E
R
V
O
L
THERMOSTATS
FAN
MOTORS
T
IGBT GATE SIGNALS
PROTECTION SIGNAL
A
G
E
THERMAL
LIGHT
CONTROL BOARD
CR1 RELAY DRIVE SIGNAL
18VAC
AUXILIARY
TRANSFORMER
REMOTE
RECEPTACLE
LOCAL/
REMOTE
SWITCH
OUTPUT
CONTROL
STRIKE
CONTROL FORCE SWITCH
CONTROL
ARC
MODE
INPUT LINE VOLTAGE
The single-phase or three-phase input power of 208,
230 or 460 volts AC is connected to the machine,
through a line switch located on the front panel.
A reconnect panel and switch allows the user to con-
figure the machine for either a low or high input volt-
age and also connect the auxiliary transformer for the
appropriate input voltage.
The auxiliary transformer develops the appropriate AC
voltages to operate the cooling fans and the control
board.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
INVERTEC V250-S
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E-3
E-3
THEORY OF OPERATION
FIGURE E.2 PROTECTION AND PRE-CHARGE CIRCUITS
MAIN
POWER BOARD
TRANSFORMER
CR1
RELAY
INPUT
RECTIFIER
INPUT
LINE
SWITCH
IGBT
POSITIVE
OUTPUT
CAPACITOR
R
TERMINAL
E
C
O
N
N
E
C
T
IGBT
IGBT
SHUNT
CURRENT
TRANSFORMER
S
W
I
T
C
H
NEGATIVE
OUTPUT
CAPACITOR
F
E
E
D
B
A
C
K
TERMINAL
F
E
E
D
B
A
C
K
IGBT
"A"
L
E
A
D
O
V
E
R
V
O
L
THERMOSTATS
FAN
MOTORS
T
IGBT GATE SIGNALS
PROTECTION SIGNAL
A
G
E
THERMAL
LIGHT
CONTROL BOARD
CR1 RELAY DRIVE SIGNAL
18VAC
AUXILIARY
TRANSFORMER
REMOTE
RECEPTACLE
LOCAL/
REMOTE
SWITCH
OUTPUT
CONTROL
STRIKE
CONTROL FORCE SWITCH
CONTROL
ARC
MODE
PRECHARGE AND PROTECTION
The input voltage is rectified and the DC voltage is
applied, through the reconnect switch, to the power
board. The power board contains precharging circuit-
ry for the safe charging of the input filter capacitors.
Once the capacitors are precharged and balanced the
control board activates the CR1 input relay which con-
nects full input power to the filter capacitors. When
the filter capacitors are fully charged they act as
power supplies for the IGBT switching circuit. The
Insulated Gate Bipolar Transistors supply the main
transformer primary windings with DC current flow.
See IGBT Operation Discussion and diagrams in
this section.
The power board also monitors the filter capacitors for
voltage balance and/or overvoltage and, if either
should occur, sends the appropriate signal to the con-
trol board to deactivate the CR1 input relay. The
machine output will also be disabled.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
INVERTEC V250-S
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E-4
E-4
THEORY OF OPERATION
FIGURE E.3 MAIN TRANSFORMER
MAIN
POWER BOARD
TRANSFORMER
CR1
RELAY
INPUT
RECTIFIER
INPUT
LINE
SWITCH
IGBT
POSITIVE
OUTPUT
CAPACITOR
R
TERMINAL
E
C
O
N
N
E
C
T
IGBT
IGBT
SHUNT
CURRENT
TRANSFORMER
S
W
I
T
C
H
NEGATIVE
OUTPUT
CAPACITOR
F
E
E
D
B
A
C
K
TERMINAL
F
E
E
D
B
A
C
K
IGBT
"A"
L
E
A
D
O
V
E
R
V
O
L
THERMOSTATS
FAN
MOTORS
T
IGBT GATE SIGNALS
PROTECTION SIGNAL
A
G
E
THERMAL
LIGHT
CONTROL BOARD
CR1 RELAY DRIVE SIGNAL
18VAC
AUXILIARY
TRANSFORMER
REMOTE
RECEPTACLE
LOCAL/
REMOTE
SWITCH
OUTPUT
CONTROL
STRIKE
CONTROL FORCE SWITCH
CONTROL
ARC
MODE
MAIN TRANSFORMER
Each IGBT pair acts as a switch assembly. Each
assembly feeds a separate, oppositely wound primary
winding of the main transformer. The reverse direc-
tions of current flow through the main transformer pri-
maries and the offset timing of the IGBT pairs induce
an AC square wave output signal at the secondary of
the main transformer.
The DC current flow through each primary winding is
redirected or “clamped” back to each respective filter
capacitor when the IGBTs are turned off. This is
needed due to the inductance of the transformer pri-
mary winding.
The primary currents also pass through the current
transformer which sends a signal to the control board.
If the primary currents are not equal the control board
compensates by adjusting the IGBT gate signals.
The firing of both IGBT pairs occurs during halves of
the 50 microsecond intervals, creating a constant 20
KHZ output.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
INVERTEC V250-S
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E-5
E-5
THEORY OF OPERATION
FIGURE E.4 OUTPUT RECTIFICATION AND CONTROL
MAIN
POWER BOARD
TRANSFORMER
CR1
RELAY
INPUT
RECTIFIER
INPUT
LINE
SWITCH
IGBT
POSITIVE
OUTPUT
CAPACITOR
R
TERMINAL
E
C
O
N
N
E
C
T
IGBT
IGBT
SHUNT
CURRENT
TRANSFORMER
S
W
I
T
C
H
NEGATIVE
OUTPUT
CAPACITOR
F
E
E
D
B
A
C
K
TERMINAL
F
E
E
D
B
A
C
K
IGBT
"A"
L
E
A
D
O
V
E
R
V
O
L
THERMOSTATS
FAN
MOTORS
T
IGBT GATE SIGNALS
PROTECTION SIGNAL
A
G
E
THERMAL
LIGHT
CONTROL BOARD
CR1 RELAY DRIVE SIGNAL
18VAC
AUXILIARY
TRANSFORMER
REMOTE
RECEPTACLE
LOCAL/
REMOTE
SWITCH
OUTPUT
CONTROL
STRIKE
CONTROL FORCE SWITCH
CONTROL
ARC
MODE
OUTPUT RECTIFICATION
AND CONTROL
The AC output from the main transformer secondary
is rectified to a DC output and applied to the output
terminals. Output voltage and current feedback infor-
mation, which is fed to the control board, is sensed at
the output terminals and shunt. The control board
monitors the panel controls and remote control recep-
tacle and compares these commands to the feedback
information to determine how the output should be
controlled to optimized welding results. The control
board controls the IGBT switching through pulse width
modulation circuitry. See IGBT Operation Discussion
in this section.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
INVERTEC V250-S
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E-6
E-6
THEORY OF OPERATION
PROTECTION CIRCUITS
Protective circuits are designed into the V250-S
machine to sense trouble and shut down the machine
before the trouble damages the internal machine com-
ponents. Both overload and thermal protection cir-
cuits are included.
OVERLOAD PROTECTION
THERMAL PROTECTION
The V250-S is electrically protected from producing
high output currents. Should the output current
exceed 290 amps, an electronic protection circuit will
reduce the current to less than 200 amps. Lincoln
Electric refers to this current reduction as “Fold Back”.
The machine will continue to produce this low current
until the protection circuit is reset. Reset occurs when
the output load is removed.
Thermostats protect the machine from excessive
operating temperatures. Excessive temperatures may
be caused by a lack of cooling air or operating the
machine beyond the duty cycle and output rating. If
excessive operating temperature should occur, the
thermostat will prevent output voltage or current and
the thermal indicator light will glow.
Thermostats are self-resetting once the machine cools
sufficiently. If the thermostat shutdown was caused
be excessive output or duty cycle and the fan is oper-
ating normally, the power switch may be left on and
the reset should occur within 15 minute period. If the
fan is not turning or the air intake louvers were
obstructed, then the power must be switched off for 15
minutes in order to reset. The fan problem or air
obstruction must be corrected.
A protection circuit is included to monitor the voltage
across the input filter capacitors. In the event that the
capacitor voltage is too high, the protection circuit will
prevent output.
On new installations, the protection circuit may pre-
vent output, due to unbalanced capacitor leakages,
providing the following circumstances are met:
1. Machine is connected for 380 - 460VAC input.
2. Machine did not have power applied for many
months.
3. Improper connections.
4. Internal component damage.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
INVERTEC V250-S
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E-7
E-7
THEORY OF OPERATION
INSULATED GATE BIPOLAR
TRANSISTOR (IGBT) OPERATION
An IGBT is a type of transistor. IGBTs are semicon-
ductors well suited for high frequency switching and
high current applications.
source, is applied to the gate terminal of the IGBT, it
is capable of conducting current. A voltage supply
connected to the drain terminal will allow the IGBT to
conduct and supply current to circuit components
coupled to the source. Current will flow through the
conducting IGBT to downstream components as long
as the positive gate signal is present. This is similar
to turning ON a light switch.
Drawing A shows an IGBT in a passive mode. There
is no gate signal, zero volts relative to the source, and
therefore, no current flow. The drain terminal of the
IGBT may be connected to a voltage supply; but since
there is no conduction the circuit will not supply cur-
rent to components connected to the source. The cir-
cuit is turned off like a light switch in the OFF position.
Drawing B shows the IGBT in an active mode. When
the gate signal, a positive DC voltage relative to the
FIGURE E.6 IGBT OPERATION
POSITIVE
VOLTAGE
APPLIED
GATE
GATE
SOURCE
SOURCE
n +
n +
n +
n +
p
BODY REGION
p
BODY REGION
DRAIN DRIFT REGION
DRAIN DRIFT REGION
n -
n -
n +
p +
BUFFER LAYER
n +
p +
BUFFER LAYER
INJECTING LAYER
INJECTING LAYER
DRAIN
DRAIN
B. ACTIVE
A. PASSIVE
INVERTEC V250-S
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E-8
E-8
THEORY OF OPERATION
PULSE WIDTH MODULATION
The term PULSE WIDTH MODULATION is used to
describe how much time is devoted to conduction in
the positive and negative portions of the cycle.
Changing the pulse width is known as MODULATION.
Pulse Width Modulation (PWM) is the varying of the
pulse width over the allowed range of a cycle to affect
the output of the machine.
The positive portion of the signal represents one IGBT
group1 conducting for 1 microsecond. The negative
portion is the other IGBT group1. The dwell time (off
time) is 48 microseconds (both IGBT groups off).
Since only 2 microseconds of the 50-microsecond
time period is devoted to conducting, the output power
is minimized.
MINIMUM OUTPUT
MAXIMUM OUTPUT
By controlling the duration of the gate signal, the IGBT
is turned on and off for different durations during a
cycle. The top drawing below shows the minimum
output signal possible over a 50-microsecond time
period.
By holding the gate signals on for 24 microseconds
each and allowing only 2 microseconds of dwell time
(off time) during the 50-microsecond cycle, the output
is maximized. The darkened area under the top curve
can be compared to the area under the bottom curve.
The more dark area under the curve, the more power
is present.
1 An IGBT group consists of two IGBT modules feeding one transformer primary winding.
FIGURE E.7 TYPICAL IGBT OUTPUTS
sec
sec
sec
48
50
sec
MINIMUM OUTPUT
sec
24
sec
sec
24
2
sec
50
MAXIMUM OUTPUT
INVERTEC V250-S
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SECTION F-1
SECTION F-1
TROUBLESHOOTING & REPAIR
TABLE OF CONTENTS
-TROUBLESHOOTING & REPAIR SECTION-
TROUBLESHOOTING AND REPAIR SECTION.........................................................................SECTION F
HOW TO USE TROUBLESHOOTING GUIDE.............................................................................F-2
PC BOARD TROUBLESHOOTING PROCEDURES ...................................................................F-3
TROUBLESHOOTING GUIDE.....................................................................................................F-4
TEST PROCEDURES
AUXILIARY TRANSFORMER TEST ...................................................................................F-11
INPUT RECTIFIER TEST ....................................................................................................F-15
POWER BOARD RESISTANCE TEST................................................................................F-19
OUTPUT DIODE TEST........................................................................................................F-23
POWER BOARD VOLTAGE TEST......................................................................................F-27
CONTROL BOARD VOLTAGE TEST..................................................................................F-31
PROTECTION CIRCUIT TEST............................................................................................F-35
CAPACITOR BALANCE TEST ............................................................................................F-39
REPAIR AND REPLACEMENT PROCEDURES
CONTROL BOARD REMOVAL AND REPLACEMENT.......................................................F-43
POWER BOARD REMOVAL AND REPLACEMENT...........................................................F-45
FILTER CAPACITOR REMOVAL AND REPLACEMENT....................................................F-49
INPUT RECTIFIER BRIDGE REMOVAL AND REPLACEMENT ........................................F-53
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT ......................................F-57
(MACHINE CODES BELOW 10150)
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT ......................................F-61
(MACHINE CODES ABOVE 10150)
MAIN TRANSFORMER REMOVAL AND REPLACEMENT ................................................F-65
(MACHINE CODES BELOW 10150)
MAIN TRANSFORMER REMOVAL AND REPLACEMENT ................................................F-71
(MACHINE CODES ABOVE 10150)
RETEST AFTER REPAIR ..........................................................................................................F-77
INVERTEC V250-S
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F-2
F-2
TROUBLESHOOTING & REPAIR
HOW TO USE TROUBLESHOOTING GUIDE
WARNING
Service and Repair should only be performed by Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and
machine operator and will invalidate your factory warranty. For your safety and to avoid
Electrical Shock, please observe all safety notes and precautions detailed throughout this
manual.
__________________________________________________________________________
This Troubleshooting Guide is provided to
help you locate and repair possible machine
malfunctions. Simply follow the three-step
procedure listed below.
Step 3. RECOMMENDED COURSE OF
ACTION
The last column labeled “Recommended
Course of Action” lists the most likely com-
ponents that may have failed in your
machine. It also specifies the appropriate
test procedure to verify that the subject
component is either good or bad. If there
are a number of possible components,
check the components in the order listed to
eliminate one possibility at a time until you
locate the cause of your problem.
Step 1. LOCATE PROBLEM (SYMPTOM).
Look under the column labeled “PROBLEM
(SYMPTOMS)”. This column describes
possible symptoms that the machine may
exhibit. Find the listing that best describes
the symptom that the machine is exhibiting.
Symptoms are grouped into the following
categories: output problems and welding
problems.
All of the referenced test procedures
referred to in the Troubleshooting Guide are
described in detail at the end of this chap-
ter. Refer to the Troubleshooting and Repair
Table of Contents to locate each specific
Test Procedure. All of the specified test
points, components, terminal strips, etc. can
be found on the referenced electrical wiring
diagrams and schematics. Refer to the
Electrical Diagrams Section Table of
Contents to locate the appropriate diagram.
Step 2. PERFORM EXTERNAL TESTS.
The second column labeled “POSSIBLE
AREAS OF MISADJUSTMENT(S)” lists the
obvious external possibilities that may con-
tribute to the machine symptom. Perform
these tests/checks in the order listed. In
general, these tests can be conducted with-
out removing the case wrap-around cover.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the
tests/repairs safely, contact the Lincoln Electric Service Department for technical trou-
bleshooting assistance before you proceed call 216-383-2531 or 1-800-833-9353.
_____________________________________________________________
OSCILLOSCOPE WARNING
WARNING
Do not use oscilloscopes and other test equipment which are powered by 115 VAC.
This equipment should not be used with inverter-type machines, such as Invertec
V250-S. There are high voltages present, which are “floating” off case ground (floating
ground). Connecting the ground lead of a test probe (which may be connected to the
case of the test equipment) to a high voltage potential presents a shock hazard as well
as the possibility of damage to the equipment in question.
_____________________________________________________________________
INVERTEC V250-S
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F-3
F-3
TROUBLESHOOTING & REPAIR
PC BOARD TROUBLESHOOTING PROCEDURES
- Remove the P.C. Board from the static-
shielding bag and place it directly into the
equipment. Don’t set the P.C. Board on or
near paper, plastic or cloth which could have
a static charge. If the P.C. Board can’t be
installed immediately, put it back in the static-
shielding bag.
WARNING
ELECTRIC SHOCK can kill.
Have an electrician install
and service this equip-
ment. Turn the input power
OFF at the fuse box before
working on equipment. Do
not touch electrically hot
- If the P.C. Board uses protective shorting
jumpers, don’t remove them until installation
is complete.
parts.
_______________________________
CAUTION: Sometimes machine failures
appear to be due to PC board failures. These
problems can sometimes be traced to poor
electrical connections. To avoid problems
when troubleshooting and replacing PC
boards, please use the following procedure:
- If you return a P.C. Board to The Lincoln
Electric Company for credit, it must be in the
static-shielding bag. This will prevent further
damage and allow proper failure analysis.
4. Test the machine to determine if the fail-
ure symptom has been corrected by the
replacement PC board.
1. Determine to the best of your technical
ability that the PC board is the most likely
component causing the failure symptom.
NOTE: It is desirable to have a spare (known
good) PC board available for PC board trou-
bleshooting.
2. Check for loose connections at the PC
board to assure that the PC board is prop-
erly connected.
NOTE: Allow the machine to heat up so that
all electrical components can reach their oper-
ating temperature.
3. If the problem persists, replace the sus-
pect PC board using standard practices to
avoid static electrical damage and electri-
cal shock. Read the warning inside the
static resistant bag and perform the follow-
ing procedures:
5. Remove the replacement PC board and
substitute it with the original PC board to
recreate the original problem.
a. If the original problem does not reap-
pear by substituting the original
board, then the PC board was not the
problem. Continue to look for bad
connections in the control wiring har-
ness, junction blocks, and terminal
strips.
P.C. Board can be dam-
aged by static electricity.
- Remove your body’s stat-
ic charge before opening
the static-shielding bag.
Wear an anti-static wrist
strap. For safety, use a 1
Meg ohm resistive cord
connected to a grounded
part of the equipment
frame.
ATTENTION
Static-Sensitive
Devices
Handle only at
Static-Safe
Workstations
b. If the original problem is recreated by
the substitution of the original board,
then the PC board was the problem.
Reinstall the replacement PC board
and test the machine.
Reusable
Container
Do Not Destroy
- If you don’t have a wrist
strap, touch an unpainted,
grounded, part of the
equipment frame. Keep touching the frame to
prevent static build-up. Be sure not to touch
any electrically live parts at the same time.
6. Always indicate that this procedure was
followed when warranty reports are to be
submitted.
NOTE: Following this procedure and writing on the
warranty report, “INSTALLED AND SWITCHED PC
BOARDS TO VERIFY PROBLEM,” will help avoid
denial of legitimate PC board warranty claims.
- Tools which come in contact with the P.C.
Board must be either conductive, anti-static or
static-dissipative.
INVERTEC V250-S
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F-4
F-4
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
Major physical or electrical damage Contact your local Lincoln
is observed when cover wrap-around Authorized Field Service Facility.
is removed.
Contact Lincoln Electric Service
Department (216)-383-2531 or
1-800-833-9353
The machine is dead - no output -
no fan.
1. The input power switch must be 1. The power switch (S1) may be
in the ON position.
faulty. Check or replace.
2. Make sure the input voltage is
correct for the machine.
2. Check for loose or broken leads
between the power switch (S1)
and the input rectifier D9. See
wiring diagram.
3. If the machine is set for single-
phase operation, inspect to
assure that the WHITE and
BLACK leads are connected
properly and the RED lead is not
connected and is insulated.
3. Perform the Auxiliary
Transformer Test.
4. Check that the input voltage set-
up switch and jumper “A” (the
reconnect auxiliary jumper) are in
the proper position for the input
voltage being applied. Refer to
Input Voltage Reconnect
Procedure in the Installation
Chapter.
5. Check continuity of the 0.6-amp
slow blow fuse located on the
reconnect panel.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-5
F-5
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
No output but the fan operates nor- 1. The mode switch must be in one 1. Perform the Auxiliary
mally.
of the SMAW modes or if in the
GTAW mode the remote trigger
circuit must be activated.
Transformer Test.
2. Check for loose or broken
connections on the high current
carrying parts of the V250-S.
(i.e., output diodes, output
terminals, shunt and main
transformer connections.)
2. The Local/Remote switch (S3)
must be in the LOCAL position
unless a remote control device is
attached to the remote
receptacle.
3. Check the continuity of the
normally closed thermostats and
associated wiring. See wiring
diagram.
3. If the machine has not been used
for a long time and is connected
for 380 VAC or higher, the
capacitors may need “condition-
ing”. See Input Filter Capacitor 4. Perform the Output Diode Test.
Conditioning.
5. Perform the Capacitor Balance
4. The machine may be overheated.
Check the thermal indicator light.
Test.
Wait for the machine to cool and 6. Perform the Protection Circuit
the thermostats to reset.
Test.
7. Perform the Power Board
Voltage Checks.
8. Perform the Control Board
Voltage Checks.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-6
F-6
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
Output turns on momentarily, then
switches off and repeats cycle.
1. Check the input voltages and
reconnection procedures. Make
sure the input voltage is correct
for the machine. See Input
1. Check Local/Remote switch (S3)
and associated wiring for loose or
faulty connections.
Voltage Reconnect Procedure. 2. Check Mode Switch (S2) and
associated wiring for loose or
2. Check or replace remote control
device. (If used)
faulty connections.
3. If the machine is connected for
380VAC input or higher, perform
the Capacitor Balance Test.
4. The power board may be faulty.
Replace.
5. The control board may be faulty.
Replace.
Remote output control not
functioning. The machine operates
normally on LOCAL control.
1. Make sure the Local/Remote
switch (S3) is in the REMOTE
position.
1. Check the Local/Remote switch
(S3) and the associated wiring.
See wiring diagram.
2. The remote control device may
be faulty. Replace.
2. Check for loose or faulty
connections at the remote control
receptacle.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-7
F-7
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
No output - Main input fuses open,
indicating excessive current draw.
1. Inspect input leads for possible
shorts or grounds or mis-connec-
tions.
1. Inspect interior of machine for
physical signs of electrical and
heat damage. Replace any dam-
aged components after conduct-
ing the following tests.
2. Install new fuses and reapply
power. If fuses open again, con-
sult a Lincoln Authorized Field
Service Facility.
2. Perform the Input Rectifier Test.
3. Perform Power Board
Resistance Test.
4. Check the reconnect switch and
associated leads for “shorts” or
faulty wiring.
The machine operates normally
when connected for 200 - 230VAC
input. There is no output when the
machine is connected to 380VAC or
higher.
1. Check the input voltage and input 1. Perform the Capacitor Balance
voltage reconnect procedures.
See Installation Section of this
manual.
Test.
2. Perform the Protection Circuit
Test.
3. Perform the Auxiliary
Transformer Test.
4. Perform the Power Board
Resistance Test.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-8
F-8
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
OUTPUT PROBLEMS
The machine will not produce more 1. This may be normal operation. If 1. Perform the Output Diode Test.
than 200 amps.
the output current exceeds 290
amps, an electronic protection
circuit will reduce the current to
less than 200 amps. The
machine will continue to produce
this low current until the
2. The control board may be faulty.
Replace.
protection circuit is reset. Reset
occurs when the output load is
removed.
2. Check the input voltage and input
voltage reconnect procedures.
See Input Voltage Reconnect
Procedure.
3. Check for loose or faulty welding
cables.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-9
F-9
TROUBLESHOOTING & REPAIR
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
WELDING PROBLEMS
Poor welding, weld settings drift, or 1. Make sure the machine settings 1. Check the operation of the mode
output power is low.
are correct for the weld process
being used.
switch (S2) and the associated
circuitry. See wiring diagram.
2. Check machine performance on 2. Check for loose or faulty connec-
LOCAL control. If OK then the
remote control device may be
faulty. Check or replace.
tions in the heavy current carrying
leads (i,e,. output diodes, output
terminals, shunt and main trans-
former.)
3. Check the input voltages and
input voltage reconnect
3. Perform Output Diode Test.
procedures. See Installation
Section of this manual.
4. Perform Control Board Voltage
Test.
Poor stick electrode welding
performance. The arc pops out.
1. Check for loose or faulty welding
cables.
1. Check for loose or faulty connec-
tions in the heavy current carrying
leads (i,e,. output diodes, output
terminals, shunt and main trans-
former.)
2. Is the electrode DRY? Try weld-
ing with another electrode from a
different container. Make sure
you have the correct electrode for
the application.
2. Perform Output Diode Test.
3. Make sure the machine settings 3. Perform Control Board Voltage
are correct for the weld process
being used.
Test.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric
Service Department for technical troubleshooting assistance before you proceed. Call 216-383-2531 or 1-800-833-9353.
INVERTEC V250-S
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F-10
F-10
NOTES
INVERTEC V250-S
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F-11
F-11
TROUBLESHOOTING & REPAIR
AUXILIARY TRANSFORMER TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will determine if the auxiliary transformer is functional when the correct primary volt-
age is applied to the primary winding.
MATERIALS NEEDED
Volt/ohmmeter
Machine wiring diagram
5/16” nut-driver
230VAC isolated power supply
INVERTEC V250-S
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F-12
F-12
TROUBLESHOOTING & REPAIR
AUXILIARY TRANSFORMER TEST (continued)
TEST PROCEDURE
4. Locate and disconnect plug J7 from
the wiring harness.
1. Remove main input power to the
V250-S.
5. Carefully apply the 230VAC isolated
supply to leads H1(1J7) and
H3(2J7) of the auxiliary transformer.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section
6. Carefully check for the presence of
the following voltages at the appro-
priate leads. See Table F.1.
3. Locate the Auxiliary Transformer just
behind the input line switch on the
lower right side of the machine.
AUXILIARY TRANSFOMER
PLUG J7
3J7
6J7
2J7
5J7
1J7
4J7
Figure F.1 Auxiliary Transformer and Plug J7.
INVERTEC V250-S
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F-13
F-13
TROUBLESHOOTING & REPAIR
AUXILIARY TRANSFORMER TEST (continued)
TABLE F.1 Auxiliary Transformer Test Points
TEST POINT
TEST POINT
EXPECTED VOLTAGE
H1 (1J7)
H2 (4J7)
200 - 208VAC
H1 (1J7)
H4 (3J7)
380 - 415VAC
H1 (1J7)
H5 (6J7)
440 - 460VAC
RED LEAD (1J1)
On Control Board
RED LEAD (3J1)
On Control Board
18VAC (SECONDARY)
7. If the correct test voltages are pre-
sent the auxiliary transformer is good.
8. If any of the voltages are missing or
very low, with the proper primary
voltage applied, the auxiliary trans-
former may be faulty. Replace.
9. If the auxiliary transformer tests good
but does not function when connect-
ed to the V250-S check the harness
wiring to the auxiliary transformer.
See wiring diagram.
INVERTEC V250-S
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F-14
F-14
NOTES
INVERTEC V250-S
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F-15
F-15
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will help determine if the input rectifier has “shorted” or “open” diodes.
MATERIALS NEEDED
Analog voltmeter/ohmmeter (Multimeter)
Phillips head screwdriver
Wiring diagram
INVERTEC V250-S
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F-16
F-16
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER TEST (continued)
TEST PROCEDURE
4. With the Phillips head screwdriver
1. Remove main input power to the
V250-S.
remove leads #207, 207A and #209
from the rectifier. See Figure F.2.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
5. Use the analog ohmmeter to perform
the tests detailed in Table F.2. See
wiring diagram.
3. Locate Input Rectifier (D9) and lead
locations.
#207
#207A
A
B
C
#209
Figure F.2 Input Rectifier and Leads.
INVERTEC V250-S
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F-17
F-17
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER TEST (continued)
TABLE F.2 Input Rectifier Test Points
TEST POINT TERMINALS
ANALOG METER X10 RANGE
+ Probe
- Probe
Acceptable Meter Readings
A
B
C
207
207
207
Greater than 1000 ohms
Greater than 1000 ohms
Greater than 1000 ohms
A
B
C
209
209
209
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
207
207
207
A
B
C
Less than 100 ohms
Less than 100 ohms
Less than 100 ohms
209
209
209
A
B
C
Greater than 1000 ohms
Greater than 1000 ohms
Greater than 1000 ohms
6. If the Input Rectifier does not meet
the acceptable readings outlined in
Table F.2. the component may be
faulty. Replace.
8. If the Input Rectifier is good be sure
to reconnect leads #207, #207A and
#209 to the correct terminals and
torque to 31IN-LBS. See wiring dia-
gram and Figure F.2.
Note: Before replacing the Input
Rectifier(D9) check the input
power switch (S1) and perform
the Power Board Resistance
Test. Also check for leaky or
faulty filter capacitors.
7. When installing a new Input
Rectifier, torque the mounting nuts to
44IN-LBS. A thin coating of Dow
Corning 340 Heat Sink Compound
(Lincoln E1868) is recommended.
Torque the lead terminals to 31IN-
LBS. See Input Rectifier Bridge
Removal And Replacement.
INVERTEC V250-S
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F-18
F-18
NOTES
INVERTEC V250-S
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F-19
F-19
TROUBLESHOOTING & REPAIR
POWER BOARD RESISTANCE TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will help determine if the Power Board has any “shorted” or “leaky” power diodes or
Insulated Gate Bipolar Transistors. Also it will help to indicate any “shorted” filter capacitors.
MATERIALS NEEDED
Analog voltmeter/ohmmeter (Multimeter)
Wiring diagram
INVERTEC V250-S
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F-20
F-20
TROUBLESHOOTING & REPAIR
POWER BOARD RESISTANCE TEST (continued)
TEST DESCRIPTION
4. Carefully remove main transformer
1. Remove main input power to the
V250 -S.
primary leads #201, #204, #205 and
#208 from the power board.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
5. Use the analog ohmmeter to perform
the tests outlined in Table F.3. See
power board schematic.
3. Locate the Power Board and associ-
ated lead locations. See Figure F.3.
201
204
+
207A
202A
DANGER
HIGH VOLTAGE CAN KILL
209
208
+
203A
206
205
Figure F.3 Power Board Test Points.
INVERTEC V250-S
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F-21
F-21
TROUBLESHOOTING & REPAIR
POWER BOARD RESISTANCE TEST (continued)
TABLE F.3 Power Board Resistance Test Points.
TEST POINT TERMINALS
ANALOG METER X10 RANGE
Acceptable Meter Readings
+ Probe
- Probe
201
207A
207A
201
Greater than 1000 ohms
Less than 100 ohms
204
207A
207A
204
Greater than 1000 ohms
Less than 100 ohms
202A
204
204
202A
Greater than 1000 ohms
Less than 100 ohms
202A
201
201
202A
Greater than 1000 ohms
Less than 100 ohms
205
203A
203A
205
Greater than 1000 ohms
Less than 100 ohms
208
203A
203A
208
Greater than 1000 ohms
Less than 100 ohms
206
208
208
206
Greater than 1000 ohms
Less than 100 ohms
206
205
205
206
Greater than 1000 ohms
Less than 100 ohms
6. If the power board does not meet the
acceptable readings outlined in
Table F.3. the board may be faulty.
Replace.
See Power Board
Removal and Replacement
Procedure.
Note: Complete power board and filter
capacitor replacement is recommended
.
7. If the power board “passes” the
resistance test proceed to the Power
Board Voltage Test.
Note: Reconnect leads #201, #204,
#205 and #208 to their appropriate ter-
minals.
INVERTEC V250-S
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F-22
F-22
NOTES
INVERTEC V250-S
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F-23
F-23
TROUBLESHOOTING & REPAIR
OUTPUT DIODES TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will help determine if any of the output diodes are “shorted”.
MATERIALS NEEDED
Analog voltmeter/ohmmeter (Multimeter)
Wiring diagram. Note: Output diode polarity will vary with machine codes.
INVERTEC V250-S
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F-24
F-24
TROUBLESHOOTING & REPAIR
OUTPUT DIODES TEST (continued)
4. Using the analog ohmmeter test for
TEST PROCEDURE
more than 200 ohms resistance
between positive and negative out-
put terminals. Positive test lead to
the positive terminal; Negative test
lead to the negative terminal. See
Figure F.5.
1. Remove main input power to the
V250-S.
2. Locate the output terminals on the
front panel of the machine. See
Figure F.4.
NOTE: THE POLARITY OF THE TEST
LEADS IS MOST IMPORTANT. IF
THE TEST LEADS POLARITY IS NOT
CORRECT THE TEST WILL HAVE
ERRONEOUS RESULTS.
3. Remove any output cables and load
from the output terminals.
SMAW
SOFT
SMAW
CRISP
GTAW
THERMAL
HOT START
5
6
4
7
3
8
9
2
A
120
85
1
OUTPUT
0
10
170
230
50
15
ARC FORCE
LOCAL
REMOTE
5
6
1
4
7
3
250
8
9
2
1
0
10
INVERTEC ® V250-S
S
I
+
-
O
NEGATIVE
OUTPUT
TERMINAL
POSITIVE
OUTPUT
TERMINAL
Figure F.4 Machine Output Terminals.
INVERTEC V250-S
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F-25
F-25
TROUBLESHOOTING & REPAIR
OUTPUT DIODES TEST (continued)
INVERTEC ® V250-S
S
I
+
-
O
Figure F.5 Meter Probes.
5. If more than 200 ohms is measured
the output diodes are not “shorted”.
8. Locate output diodes and snubbers.
See Figure F.6. for machine codes
10102 and 10103 only. See Figure
F.7. for machine codes 10187 and
10188 only.
6. If less than 200 ohms is measured,
one or more output diodes or snub-
bers may be shorted or “leaky”.
9. Test all output diodes and snubbers
(if used) individually.
7. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
INVERTEC V250-S
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F-26
F-26
TROUBLESHOOTING & REPAIR
OUTPUT DIODES TEST (continued)
OUTPUT DIODES
SNUBBERS
Figure F.6 Output Diodes and Snubber Locations (Codes 10102 and 10103)
DIODE MODULES
Figure F.7 Output Diode Module Locations (Codes 10187 and 10188)
INVERTEC V250-S
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F-27
F-27
TROUBLESHOOTING & REPAIR
POWER BOARD VOLTAGE TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will aid the technician in determining if the voltage board or some other machine
component may be faulty.
MATERIALS NEEDED
Voltmeter/ohmmeter (Multimeter)
Wiring diagram.
Power board schematic drawing.
INVERTEC V250-S
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F-28
F-28
TROUBLESHOOTING & REPAIR
POWER BOARD VOLTAGE TEST (continued)
4. The following tests will be performed
TEST PROCEDURE
with the input power applied to the
V250-S. BE CAREFUL. ALWAYS
REMOVE INPUT POWER AND
PERFORM FILTER CAPACITOR
1. Remove main input power to the
V250-S.
DISCHARGE
PROCEDURE
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
BEFORE
TOUCHING ANY
MACHINE COMPONENT.
5. Apply input power and turn On the
V250-S.
3. Locate and familiarize yourself with
the leads and pin locations in plug J6
on the power board. See Figure F.8.
6. Perform the voltage checks outlined
in Table F.4. making sure all of the
test conditions are in effect.
#313 (5J6)
#309 (6J6)
#310 (3J6)
#311 (4J6)
#308 (1J6)
#307 (2J6)
PLUG J6
V2WER G2684
Figure F.8 Plug J6 on Power Board
INVERTEC V250-S
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F-29
F-29
TROUBLESHOOTING & REPAIR
POWER BOARD VOLTAGE TEST (continued)
TABLE F.4. Power Board Voltage Test Points.
ACCEPTABLE
TEST DESCRIPTION
TEST POINTS
VOLTAGES
TEST CONDITIONS
The PWM pulse drive from the
control board to the pulse
transformer primary located on
the power board.
Lead #307 (2J6)
to
Negative output terminal
14VDC.
No load on the machine - the
mode switch in SMAW posi-
tion.
The PWM pulse drive from the
control board to the pulse
transformer primary located on
the power board.
Lead #308 (1J6)
to
Negative output terminal
14VDC.
7VDC.
7VDC.
No load on the machine - the
mode switch in SMAW posi-
tion.
The PWM pulse drive from the
control board to the pulse
transformer primary located on
the power board.
Lead #307 (2J6)
to
Negative output terminal
Machine loaded to 250Amps.
The output control R3 at the
maximum position.
The PWM pulse drive from the
control board to the pulse
transformer primary located on
the power board.
Lead #308 (1J6)
to
Negative output terminal
Machine loaded to 250Amps.
The output control R3 at the
maximum position.
CR1 (charge relay) coil volt-
age.
Lead #309 (6J6)+
to
lead #310 (3J6)
12VDC
This voltage should be pre-
sent only after the protection
circuit as been satisfied.
This low voltage will be pre-
sent when the protection cir-
cuit has determined that the
filter capacitor voltage is
acceptable. Note: The CR1
charge relay should be acti-
vated.
Lead #311 (4J6)+
to
lead #313 (5J6)-
0 to 1VDC.
If voltage protection circuit IS
satisfied.
This voltage will be present
unit the protection circuit
determines that the filter
capacitor is at an acceptable
level.
Lead #311 (4J6)+
to
lead #313 (5J6)-
15VDC.
If voltage protection circuit is
NOT satisfied.
Note: The CR1 charge relay
will not be activated.
INVERTEC V250-S
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F-30
F-30
NOTES
INVERTEC V250-S
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F-31
F-31
TROUBLESHOOTING & REPAIR
CONTROL BOARD VOLTAGE TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will aid the technician in determining if the control board or some other machine
component may be faulty.
MATERIALS NEEDED
Voltmeter/ohmmeter (Multimeter)
Wiring diagram.
Control board schematic drawing.
INVERTEC V250-S
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F-32
F-32
TROUBLESHOOTING & REPAIR
CONTROL BOARD VOLTAGE TEST (continued)
4. The following tests will be performed
TEST PROCEDURE
with the input power applied to the
V250-S. BE CAREFUL. ALWAYS
REMOVE INPUT POWER AND
PERFORM FILTER CAPACITOR
1. Remove main input power to the
V250-S.
DISCHARGE
PROCEDURE
2. Perform
Filter Capacitor
BEFORE
TOUCHING ANY
Discharge Procedure detailed in
Maintenance Section.
MACHINE COMPONENT.
5. Apply input power and turn ON the
V250 -S.
3. Locate and familiarize yourself with
the leads and pin locations in plugs
J1 thru J5 on the control board. See
Figure F.9.
6. Perform the voltage checks outlined
in Table F.5. making sure all of the
test conditions are in effect.
7J3
(#303)
1J3
(#375)
1J5
(#322)
1J1
(RED LEAD)
1J4
(BLACK LEAD)
2J4
(WHITE LEAD)
3J1
(RED LEAD)
J1
J2
J5
J3
J4
4J5
(#318)
G2666-[ ]
V250S CONTROL
Figure F.9 Plugs J1-J5 on Control Board
INVERTEC V250-S
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F-33
F-33
TROUBLESHOOTING & REPAIR
CONTROL BOARD VOLTAGE TEST (continued)
TABLE F.5. Control Board Voltage Test Points.
ACCEPTABLE
TEST DESCRIPTION
TEST POINTS
VOLTAGES
TEST CONDITIONS
The 18VAC from the auxil-
iary transformer to the con-
trol board.
Red lead (1J1)
to
Red lead (3J1)
18VAC
The correct input voltage
Note: voltage will vary with applied to the V250-S and
input line voltage.
the input power switch (S1)
in the ON position.
Remote trigger circuit test.
(#2 and #4)
Lead #318 (4J5)
to
0 VDC.
When remote trigger circuit
is “closed”.
Lead #322 (1J5)
Remote trigger circuit test.
(#2 and #4)
Lead #318 (4J5)
to
Lead #322 (1J5)
12VDC.
100 mV.
15VDC.
When remote trigger circuit
is “open”.
Shunt feedback milli-volt
check.
White lead (2J4)+
to
Black lead (1J4)-
Machine loaded to 120
Amps
Check for 15VDC control
board supply voltage.
Lead #303 (7J3)+
to
Lead #375 (1J3)-
The correct input voltage
applied to the V250-S and
the input power switch (S1)
in the ON position.
INVERTEC V250-S
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F-34
F-34
NOTES
INVERTEC V250-S
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F-35
F-35
TROUBLESHOOTING & REPAIR
PROTECTION CIRCUIT TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This check will aid the technician in the understanding and evaluation of the V250-S protec-
tion circuit.
MATERIALS NEEDED
Voltmeter/ohmmeter (Multimeter)
Machine wiring diagram
Protection circuit simplified wiring diagram
INVERTEC V250-S
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F-36
F-36
TROUBLESHOOTING & REPAIR
PROTECTION CIRCUIT TEST (continued)
3. Locate and familiarize yourself with
TEST PROCEDURE
1. Remove main input power to the
V250-S.
the leads and pin locations in plug J2
on the control board and also plug
J6 on the power board. See Figures
F.10. and F.11.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
8J2
6J2
J1
J2
J5
J3
J4
1J2
2J2
G2666-[ ]
V250S CONTROL
Figure F.10 Control Board Plug J2 Test Points
#313 (5J6)
#309 (6J6)
#311 (4J6)
#308 (1J6)
#310 (3J6)
#307 (2J6)
PLUG J6
V2WER G2684
Figure F.11 Power Board Plug J6 Test Points
INVERTEC V250-S
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F-37
F-37
TROUBLESHOOTING & REPAIR
PROTECTION CIRCUIT TEST (continued)
4. The following tests will be performed
with the input power applied to the
V250-S. BE CAREFUL. ALWAYS
REMOVE INPUT POWER AND
PERFORM FILTER CAPACITOR
If the correct voltage is present at
the power board but not at the control
board check associated leads and
connections.
DISCHARGE
PROCEDURE
8. Check for 15VDC at leads
#309(1J2)+ to #310(6J2)- at the con-
trol board. If the correct voltage is
present check for 15VDC at leads
#309(6J6) + to #310(3J6)- at the
power board.
BEFORE
TOUCHING ANY
MACHINE COMPONENT.
5. Apply input power and turn ON the
V250-S.
6. Check for 0 to 1 VDC at leads
#311(4J6)+ to #313(5J6)- at the
power board. If the correct voltage
is present go to step #7.
If the correct voltage is present at the
control board but not at the power
board check the associated leads
and connections.
If 15VDC is present the overvoltage
protection circuit has not been satis-
fied. Perform the Capacitor Balance
Test. If the capacitor balance is
good and the overvoltage protection
circuit has NOT been satisfied the
power board may be faulty. Replace.
If the correct voltage, 15VDC, is not
present at the control board the con-
trol board may be faulty. Perform the
Control Board Voltage Test.
9. If 15VDC IS present at leads
#309(6J6)+ to #310(3J6)- at the
power board the input relay
(1CR), should activate (pull-in) and
apply full input power to the filter
capacitors.
7. Check for 0 to 1VDC at leads
#311(2J2)+ to #313(8J2)- at the con-
trol board. If the correct voltage is
present go to step 8.
If this does not take place the power
board may be faulty. Replace.
PROTECTION CIRCUIT (SIMPLIFIED)
POWER BOARD
CONTROL BOARD
+15VDC
TIMER
#311
#313
(4J6)
(5J6)
(2J2)
(8J2)
O
V
E
R
V
O
L
D
E
T
E
C
T
I
T
O
N
A
G
E
+15VDC
#309
#310
(6J6)
(3J6)
(1J2)
(6J2)
1CR
CHARGE
RELAY
INVERTEC V250-S
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F-38
F-38
NOTES
INVERTEC V250-S
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F-39
F-39
TROUBLESHOOTING & REPAIR
CAPACITOR BALANCE TEST
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
TEST DESCRIPTION
This test will help the technician to determine if the input filter capacitors are being charged
equally and to the correct voltage levels. Note: This test should only be conducted with the
V250-S reconnect switch and “A” jumper configured for 380VAC and above.
MATERIALS NEEDED
Voltmeter/ohmmeter (Multimeter)
Machine wiring diagram.
INVERTEC V250-S
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F-40
F-40
TROUBLESHOOTING & REPAIR
CAPACITOR BALANCE TEST (continued)
6. The following tests will be performed
TEST PROCEDURE
with the input power applied to the
V250-S. BE CAREFUL. ALWAYS
REMOVE THE INPUT POWER AND
PERFORM FILTER CAPACITOR
DISCHARGE PROCEDURE
1. Remove main input power to the
V250-S.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
BEFORE TOUCHING ANY
MACHINE COMPONENT.
†
3. Put the mode switch S2 in the
SMAW (soft) position and put the
Local/Remote switch S3 in the
LOCAL position.
7. Apply the correct input power and
turn ON the V250-S.
4. Put the Output Control R3 at the
minimum position.
† Note: This test should only be conducted
with the V250-S reconnect switch and “A”
jumper configured for 380VAC and above.
5. Locate and familiarize yourself with
the capacitor test locations on the
power board. See Figure F.12.
CAPACITOR (C2) TERMINALS
201
+
204
207A
202A
DANGER
HIGH VOLTAGE CAN KILL
209
208
+
203A
206
205
CAPACITOR (C1) TERMINALS
Figure F.12 Power Board and Capacitor Test Locations
INVERTEC V250-S
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F-41
F-41
TROUBLESHOOTING & REPAIR
CAPACITOR BALANCE TEST (continued)
8. Check for the appropriate voltages
outlined in Table F.6. Note:
Voltages may vary with the input
line voltage.
9. If the capacitor voltages are NOT
balanced within 20VDC the capaci-
tors may be need “conditioning” .
See maintenance section.
In the event the capacitor voltage is
too high or not balanced (within
20VDC) the protection circuit will pre-
vent output. The overvoltage trip set-
ting is nominal line voltage (230/460)
+15%. Reset occurs about 3% lower
(230/460) +12%.
The capacitors or other components
on the power board may be faulty.
Replace power board.
TABLE F.6 Capacitor Voltages
EXPECTED VOLTS
DC AT CAPACITOR
TERMINALS
INPUT APPLIED
460VAC
440VAC
415VAC
380VAC
325VDC
311VDC
293VDC
269VDC
NOTE
The following machine parts must be replaced in matched sets If
Capacitor C1 is found to be defective, both Capacitors C1 and C2
must be replaced at the same time:
INVERTEC V250-S
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F-42
F-42
NOTES
INVERTEC V250-S
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F-43
F-43
TROUBLESHOOTING & REPAIR
CONTROL BOARD REMOVAL AND REPLACEMENT
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
Small needle-nose pliers
Small screwdriver
5/16” nut-driver
INVERTEC V250-S
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F-44
F-44
TROUBLESHOOTING & REPAIR
CONTROL BOARD REMOVAL AND REPLACEMENT (continued)
Note: Be sure to observe static elec-
tricity precautions when handling
PROCEDURE
P.C. boards.
1. Remove input power to the V250-S.
6. When replacing the control board
align the mounting holes with the
mounting pins and gently slide the
P.C. board onto the mounting pins
until the board “snaps” onto the
mounting pins.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
3. Locate the control board and the five
molex type plugs that are connected
to it. See Figure F.13.
Note: Be sure to observe static elec-
tricity precautions when handling
P.C. boards.
4. Carefully remove the five molex type
plugs by depressing the locking tabs
and gently extracting the plugs from
the P.C. board receptacles.
7. Replace the five molex type plugs in
their appropriate receptacles.
5. Using the needle nose-pliers and
small screwdriver gently remove the
control board from the six mounting
pins by depressing the tabs on the
mounting pins and sliding the board
from the pins. See Figure F.13.
8. Inspect, clear and secure all leads in
preparation for case wrap-around
reassembly.
9. Using the 5/16” nut-driver replace
the case wrap-around.
J1
J2
J5
J3
J4
SIX MOUNTING TABS
G2666-[ ]
V250S CONTROL
DEPRESS LOCKING TAB
ON MOUNTING PIN
Figure F.13 Control Board Plugs and Mounting Pins
INVERTEC V250-S
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F-45
F-45
TROUBLESHOOTING & REPAIR
POWER BOARD REMOVAL AND REPLACEMENT
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
5/16” nut-driver
1/4” nut-driver
7/16” wrench
3/16” Allen type wrench
INVERTEC V250-S
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F-46
F-46
TROUBLESHOOTING & REPAIR
POWER BOARD REMOVAL AND REPLACEMENT (continued)
5. Remove plug J6 by depressing the
PROCEDURE
locking tab and removing it from the
power board.
1. Remove input power to the V250-S.
6. With the 7/16” wrench remove the
four bolts and washers from the filter
capacitor terminals.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
Remove leads #202A, #207A,
#203A and #206 from the capacitor
terminals.
3. Locate the power board, the molex
type plug J6, the five leads with
push-on connectors and the four
capacitor leads that are connected to
the power board.
See Figure F.14. Cut any neces-
sary cable ties.
4. Carefully remove leads (with push-
on connectors) #201, #204, #205,
#208, and #209 from the power
board.
201
+
204
207A
202A
4 SOCKET HEAD
CAP SCREWS
DANGER
HIGH VOLTAGE CAN KILL
J6
209
+
208
203A
206
205
Figure F.14 Power Board Lead Locations
INVERTEC V250-S
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F-47
F-47
TROUBLESHOOTING & REPAIR
POWER BOARD REMOVAL AND REPLACEMENT (continued)
7. Using the 1/4” nut-driver remove the
two screws holding the P.C. board to
the heat sink mounting bracket.
13. Assemble the leads #202A, #207A,
#203A and #206 to their respective
capacitor terminals using the bolts,
lockwashers and 7/16” wrench.
Torque to 50 - 60 IN. Lbs.
8. With the 3/16” Allen wrench remove
the four socket head cap screws and
washers holding the power board to
the large aluminum heat sink.
14. Using the 1/4” nut-driver install the
two screws holding the P.C. board
to the heat sink mounting bracket.
9. Carefully remove the power board
taking note as to the amount of heat
sink compound used between the
IGBTs and the large aluminum heat
sink. Note: Be sure to observe static
electricity precautions when handling
P.C. boards.
15. Connect leads #201, #204, #205,
#208, and #209 to their appropriate
terminals.
16. Replace plug J6 into power board.
17. Replace any previously removed
cable ties.
If the filter capacitors are to be
removed see Filter Capacitor
Removal and Replacement.
18 Inspect, clear and secure all leads
in preparation for case wrap-around
reassembly.
POWER BOARD REPLACEMENT
PROCEDURE
10. Apply a thin coat of Dow Corning
340 heat sink compound (Lincoln
E1868) to the filter capacitor termi-
nals. Do not apply to screw threads
or threaded area of terminals.
11. When replacing the power board
apply a thin coating (.005 to .010)
of Dow Corning 340 heat sink
compound (Lincoln E1868) to the
mating surfaces between the
IGBTs and the aluminum heat
sink. Compound is NOT permitted
on the screw heads or mounting
hole threads. The mating surfaces
must be clean and free of any for-
eign material.
12. Install the power board and tighten
the four cap head screws. Torque
the cap head screws to 40 to 48 IN.
Lbs. Note: Before tightening make
certain the capacitor terminals are
aligned with their respective holes
in the power P.C. board.
INVERTEC V250-S
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F-48
F-48
NOTES
INVERTEC V250-S
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F-49
F-49
TROUBLESHOOTING & REPAIR
FILTER CAPACITOR REMOVAL AND REPLACEMENT
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
5/16” nut-driver
Slot head screwdriver
MATCHED PARTS
The following machine parts must be replaced in matched sets If Capacitor C1 is found to be
defective, both Capacitors C1 and C2 must be replaced at the same time:
INVERTEC V250-S
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F-50
F-50
TROUBLESHOOTING & REPAIR
FILTER CAPACITOR REMOVAL AND REPLACEMENT (continued)
5. Using the 5/16” nut-driver remove
PROCEDURE
the two screws from the top front of
the case front panel. See Figure
F.15.
1. Remove input power to the V250-S.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
6. Using the slot head screwdriver
carefully
disengage
the
heatsink/power board mounting
bracket from the top center panel.
This can be accomplished by sliding
the bracket assembly towards the
rear of the machine while at the
some time gently lifting up on the top
center panel. See Figure F.15.
3. Perform Power Board Removal
Procedure in this section.
4. Using the 5/16’ nut-driver remove
the two screws from the top rear of
the case back. See Figure F.15.
TOP CENTER PANEL
MOUNTING BRACKETS
REMOVE
CASE BACK
SCREWS
REMOVE
CASE FRONT
SCREWS
POWER BOARD
Figure F.15 Heatsink/Power Board Removal
INVERTEC V250-S
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F-51
F-51
TROUBLESHOOTING & REPAIR
FILTER CAPACITOR REMOVAL AND REPLACEMENT (continued)
7. Once the top of the bracket assem-
bly is disengaged from the top center
panel the bracket assembly can be
removed from the bottom of the case
by sliding the bracket assembly
towards the front of the machine.
The locking tab on the bottom of the
bracket will have to be lifted slightly
to enable the assembly to slide
freely towards the front.
11. Install the heatsink/power board
bracket assembly (with new capaci-
tors
installed)
into
the
machine by first positioning the
bottom of the bracket into the slots
in the case bottom and sliding the
bracket assembly towards the rear
of the machine.
12. Carefully position the top of the
heatsink/power board bracket
assembly into the top center panel
and slide the panel towards the
rear of the machine while holding
the heatsink/power board mounting
bracket in place.
8. With the bracket assembly out of the
machine the filter capacitors can be
removed by loosening the capacitor
clamps and sliding the filter capaci-
tors out of the assembly.
Note: Before removing the capaci-
tors precisely mark where the capac-
itors are positioned in the clamp.
This is important so the new capaci-
tor terminals will align with the holes
in the power board. Also mark
13. Using the 5/16’ nut-driver replace
the two screws at the top rear of
the case back. See Figure F.15.
14. Using the 5/16” nut-driver replace
the two screws at the top front of
the case front panel. See Figure
F.15.
polarity
configuration
for
reassembly purposes.
9. Install the new capacitors taking note
of position in the clamp and also
polarity location.
15. Perform
Power
Board
Replacement Procedure in this
section.
10. Using the slot head screwdriver
tighten the clamps.
INVERTEC V250-S
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F-52
F-52
NOTES
INVERTEC V250-S
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F-53
F-53
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER BRIDGE REMOVAL AND REPLACEMENT
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
3/16” Allen type wrench
Phillips head screwdriver
7/16” Box wrench
Torque wrench
INVERTEC V250-S
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F-54
F-54
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER BRIDGE REMOVAL AND REPLACEMENT (continued)
5. With the Phillips head screwdriver
PROCEDURE
remove the eight leads connected to
the rectifier terminals.
1. Remove input power to the V250-S.
6. Using the 3/16” Allen wrench and
7/16” box wrench remove the two
cap head screws, washers and nuts
mounting the input rectifier bridge to
the center panel assembly.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
3. Locate the input rectifier and the
leads connected to it. See Figure
F.16.
4. Identify and mark the leads connect-
ed to the rectifier terminals.
CAP HEAD
MOUNTING
SCREWS
#207
#207A
A
B
C
#209
Figure F.16 Input Rectifier Lead Locations
INVERTEC V250-S
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F-55
F-55
TROUBLESHOOTING & REPAIR
INPUT RECTIFIER BRIDGE REMOVAL AND REPLACEMENT (continued)
7. Carefully remove the input rectifier
bridge.
8. When installing a new input rectifier
apply a thin coating of Dow Corning
340 Heat Sink Compound (Lincoln
E1868) to the mating surfaces.
Torque the mounting cap screws
and nuts to 44 IN-LBS.
9. Reconnect the eight leads to the cor-
rect terminals and torque the phillips
head screws to 31 IN-LBS.
INVERTEC V250-S
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F-56
F-56
NOTES
INVERTEC V250-S
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F-57
F-57
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
Slot head screwdriver
5/16” nut-driver
7/16” wrench
Wire cutters
3/8” wrench
INVERTEC V250-S
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F-58
F-58
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
6. Using the 7/16” wrench remove the
PROCEDURE
bolts, nuts and washers from two of
the splices.
1. Remove input power to the V250-S.
7. Using the 3/8” wrench and slot head
screwdriver disassemble the other
two splices.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
8. Using the 7/16” wrench remove the
bolt and washers connecting the out-
put cable to the diode heat sink. Be
sure to take note of the small resistor
connection at the same point. See
Figure F.17.
3. Locate output diode assembly and
associated leads. See Figure F.17.
4. Cut the necessary wire ties and slide
the sleeving from the four wire con-
nections to be disassembled. See
Figure F.17
9. With the 5/16” nut-driver remove the
two screws from the top rear case
back. See Figure F.15.
5. Label the leads for identification pur-
poses for reassembly.
SNUBBER RESISTORS
7/16 BOLT
SLEEVED SPLICES
Figure F.17 Output Diode Assembly and Leads
INVERTEC V250-S
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F-59
F-59
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
LOCKING TABS
Figure F.18 Heatsink Removal
15. Install the two screws into the top
10. Using the slot head screwdriver
carefully disengage the output
diode heat sink mounting bracket
from the top center panel. Also dis-
engage the bottom heat sink
mounting bracket from the support
bracket. This can be accomplished
by lifting the locking tab and sliding
the heat sink assembly towards the
rear of the machine. See Figure
F.18.
rear case back. See Figure F.15.
16 Using the 7/16” wrench, bolt and
washers connect the output cable to
the diode heat sink. Be sure to take
note of the small resistor connection
at the same point. See Figure
F.17.
17. Using the 7/16” wrench, bolts, nuts
and washers assemble and tighten
the two splices.
11. Carefully remove the output diode
assembly from the V250-S.
18. Using the 3/8” wrench and slot
head screwdriver assemble and
tighten the other two splices.
12. Remove the two heat sink holders
from the heat sink/diode assembly.
19. Position sleeving and secure with
cable ties. Clear all leads and pre-
pare unit for reassembly of wrap-
around case.
13. Assemble the two heat sink holders
to the new heat sink/diode assem-
bly.
14. Install the new output diode assem-
bly into position and slide it towards
the front of the machine until the
locking tabs (both top and bottom)
are engaged. See Figure F.18.
INVERTEC V250-S
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F-60
F-60
NOTES
INVERTEC V250-S
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F-61
F-61
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
7/16” wrench
1/8” Allen type wrench
Torque wrench
INVERTEC V250-S
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F-62
F-62
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
5. Using the 7/16” wrench remove the
PROCEDURE
bolts, nuts and washers from the
lead terminals of the module to be
replaced. Clear leads and take care-
ful note of lead placement.
1. Remove input power to the V250-S.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
3. Locate output diode assembly and
associated leads. See Figure F.19.
4. Label the leads for identification pur-
poses for reassembly.
7/16 MOUNTING BOLTS
DIODE MODULES
7/16 BOLTED CONNECTIONS
Figure F.19 Output Diode Assembly and Leads
INVERTEC V250-S
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F-63
F-63
TROUBLESHOOTING & REPAIR
OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
6. Using 7/16” wrench remove the top
and bottom mounting bolts and
associated washers from the diode
module to be replaced.
13. Run the center cap screw in by
hand until it makes contact with the
surface of the module. Do not
torque down yet!
7. Using 1/8” Allen wrench remove the
center socket head cap screw from
the diode module to be replaced.
14. Tighten the top and bottom screws
to between 5.0 and 10.0 IN-LBS.
15. Tighten the center cap screw to
between 12 and 18 IN-LBS.
8. Carefully remove the diode module.
9. To install the new module first make
sure the heat sink surface is clean
and free of dirt.
16. Further tighten the top and bottom
screws to between 30 and 40
IN-LBS.
10. Apply a thin even coating (.004 to
.010 IN.) of thermal compound
Penetrox A13 (Lincoln E2529) to
the bottom surface of the base
plate. Keep the compound away
from the mounting hole areas.
17. Connect the leads to the proper ter-
minals and tighten the screws to
between 30 to 40 IN-LBS. Do not
stress the module terminals when
making these connections.
18. Clear all leads and prepare unit for
reassembly of wrap-around case.
11. Apply a small amount of Loctite
#271 (Lincoln E1777-1) to the first
three threads of the socket head
cap screw.
12. Start threading the top and bottom
screws and associated washers by
hand. Also start the center socket
head cap screw and associated
washer.
INVERTEC V250-S
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F-64
F-64
NOTES
INVERTEC V250-S
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F-65
F-65
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
7/16” Wrench
3/8” Wrench
Wire cutters
3/4” Wrench
Slot head screwdriver
INVERTEC V250-S
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F-66
F-66
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
cable ties. Be sure to note the
direction that the leads are thread-
PROCEDURE
ed through the current trans-
former. Upon reassembly the
1. Remove input power to the V250-S.
leads must be threaded through
correctly.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
5. Locate main transformer and associ-
ated secondary leads, reactor leads,
and shunt connections. See Figure
F.21.
3. Locate main transformer and associ-
ated primary leads. See Figure F.20.
4. Disconnect transformer primary
leads #201, #204, #205 and #208
from the power board.
Note: Leads #204 and #205 will
have to be removed from the T3 cur-
rent transformer. Cut any necessary
201
204
208
205
T3 CURRENT TRANSFORMER
MAIN TRANSFORMER
Figure F.20 Main Transformer Right Side
INVERTEC V250-S
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F-67
F-67
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
MAIN TRANSFORMER
SECONDARY LEADS
Figure F.21 Main Transformer Left Side
6. Disconnect and clear the shunt
sensing leads from the control board
(plug J4).
10. Locate and cut the necessary wire
ties and slide the sleeving from the
four transformer secondary and
reactor lead splices.
7. Disconnect the thermostat leads
from the thermostat mounted on the
shunt assembly.
11. With slot head screwdriver and 3/8”
nut-driver remove the two reactor
leads from output rectifier leads.
Label the leads for reassembly.
8. With the 3/4” wrench remove the
shunt assembly from the negative
output terminal. Take note of the by-
pass connection on the negative ter-
minal. Clear the shunt to allow
access to the main transformer and
lead connections. Cut any neces-
sary cable ties.
12. Using the 7/16” wrench remove the
secondary leads from the output
rectifier leads.
Label the leads and note washer
and lead placement for reassembly.
9. With the 3/4” wrench remove the two
secondary leads from the positive
output terminal. Take note of the by-
pass connection on the positive ter-
minal.
13. With 3/8” wrench remove the two
screws mounting the transformer
assembly to the base of the
machine. See Figure F.22. Note:
The machine will have to be tilted
on its side to gain access to the
bottom of the unit.
INVERTEC V250-S
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F-68
F-68
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
MAIN TRANSFORMER
LOCKING MOUNTING TABS
MAIN TRANSFORMER
MOUNTING SCREWS
Figure F.22 Main Transformer Mountings
14. Using the slot head screwdriver
unclip the locking tabs and slide the
transformer towards the front of the
machine until it is free of the slots in
the bottom of the machine.
Note: The machine will have to be
tilted on its side to gain access to
the bottom of the unit.
18. Using the 7/16” wrench reassemble
the two secondary leads to the out-
put rectifier leads. Note lead and
washer placement and lead labels.
Note: The machine will have to be
tilted on its side to gain access to
the bottom of the unit.
19. Using the slot head screwdriver
and 3/8” nut-driver reassemble the
two reactor leads to the output rec-
tifier leads. Note lead labels.
15. With the main transformer loose
from the base carefully tilt and
remove the transformer from the
left side of the machine.
20. Replace the sleeving on the four
connections and replace the cable
ties.
16. Install the new transformer by tilting
and carefully positioning it in place
in the slots in the case bottom.
Slide towards the rear of the
machine until the locking tabs are
in place.
21. With the 3/4” wrench assemble the
two secondary leads to the positive
output terminal.
17. With the 3/8” wrench replace the
two transformer mounting screws.
Take note of the by-pass connec-
tion on the positive output terminal.
INVERTEC V250-S
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F-69
F-69
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES BELOW 10150)
(continued)
22. Reassemble the shunt assembly to
the negative output terminal. Take
note of the by-pass connection on
the negative terminal. Clear leads
and install any necessary cable
ties.
23. Connect the two thermostat leads.
24. Connect the shunt sensing leads to
the control board (plug J4).
25. Connect primary leads #201, #204,
#205 and #208 to the power board.
Be sure leads #204 and #205 are
routed through the current trans-
former (T3) in the correct man-
ner. Secure leads with cable ties.
26. Clear all leads and secure for case
wrap-around assembly.
INVERTEC V250-S
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F-70
F-70
NOTES
INVERTEC V250-S
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F-71
F-71
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
WARNING
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
MATERIALS NEEDED
7/16” Wrench
3/8” Wrench
Wire cutters
3/4” Wrench
Slot head screwdriver
INVERTEC V250-S
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F-72
F-72
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
rent transformer. Cut any necessary
cable ties. Be sure to note the
PROCEDURE
direction that the leads are thread-
ed through the current trans-
former. Upon reassembly the leads
must be threaded correctly.
1. Remove input power to the V250-S.
2. Perform Filter Capacitor Discharge
Procedure detailed in Maintenance
Section.
5. Locate main transformer and associ-
ated secondary leads, reactor leads,
and shunt connections. See Figure
F.24.
3. Locate main transformer and associ-
ated primary leads. See Figure
F.23.
6. Disconnect and clear the shunt
sensing leads from the control board
(plug J4).
4. Disconnect transformer primary
leads #201, #204, #205 and #208
from the power board.
NOTE: Leads #204 and #205 will
have to be removed from the T3 cur-
201
204
208
205
T3 CURRENT TRANSFORMER
MAIN TRANSFORMER
Figure F.23 Main Transformer Right Side
INVERTEC V250-S
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F-73
F-73
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
MAIN TRANSFORMER
SECONDARY LEADS
Figure F.24 Main Transformer Left Side
7. Disconnect the thermostat leads
from the thermostat mounted on the
shunt assembly.
11. With slot head screwdriver and 3/8”
nut-driver remove the two reactor
leads from output the rectifier
leads.
Label the leads for
8. With the 3/4” wrench remove the
shunt assembly from the negative
output terminal. Take note of the by-
pass connection on the negative ter-
minal. Clear the shunt to allow
access to the main transformer and
lead connections. Cut any neces-
sary cable ties.
reassembly.
12. Using the 7/16” wrench remove the
four secondary leads from the out-
put rectifier module. Label the leads
and note washer and lead place-
ment for reassembly. See Figure
F.24.
9. With the 3/4” wrench remove the
positive output lead from the positive
output terminal. Take note of the by-
pass connection on the positive ter-
minal.
13. With 3/8” wrench remove the two
screws mounting the transformer
assembly to the base of the
machine. See Figure F.25. Note:
The machine will have to be tilted
on its side to gain access to the
bottom of the unit.
10. Locate and cut the necessary wire
ties and slide the sleeving from the
two transformer reactor lead
splices.
INVERTEC V250-S
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F-74
F-74
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
MAIN TRANSFORMER
LOCKING MOUNTING TABS
MAIN TRANSFORMER
MOUNTING SCREWS
Figure F.25 Main Transformer Mountings
14. Using the slot head screwdriver
unclip the locking tabs and slide the
transformer towards the front of the
machine until it is free of the slots in
the bottom of the machine. Note:
The machine will have to be tilted
on its side to gain access to the
bottom of the unit.
18. Using the 7/16” wrench reassemble
the four secondary leads to the out-
put rectifier module. Note lead and
washer placement and lead labels.
Tighten to between 30 and 40 IN-
LBS.
Do not stress the module terminals
when making these connections.
15. With the main transformer loose
from the base carefully tilt and
remove the transformer from the
left side of the machine.
19. Using the slot head screwdriver
and 3/8” nut-driver reassemble the
two reactor leads to the output rec-
tifier leads. Note lead labels.
16. Install the new transformer by tilting
and carefully positioning it in place
in the slots in the case bottom.
Slide towards the rear of the
machine until the locking tabs are
in place.
20. Replace the sleeving on the reactor
connections and replace the cable
ties.
17. With the 3/8” wrench replace the
two transformer mounting screws.
Note: The machine will have to be
tilted on its side to gain access to
the bottom of the unit.
INVERTEC V250-S
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F-75
F-75
TROUBLESHOOTING & REPAIR
MAIN TRANSFORMER REMOVAL AND REPLACEMENT
(MACHINE CODES ABOVE 10150)
(continued)
21. With the 3/4” wrench assemble the
positive output lead to the positive
output terminal.
Take note of the by-pass connec-
tion on the positive output terminal.
22. Reassemble the shunt assembly to
the negative output terminal. Take
note of the by-pass connection on
the negative terminal. Clear leads
and install any necessary cable
ties.
23. Connect the two thermostat leads.
24. Connect the shunt sensing leads to
the control board (plug J4).
25. Connect primary leads #201, #204,
#205 and #208 to the power board.
Be sure leads #204 and #205 are
routed through the current trans-
former (T3) in the correct man-
ner.
Secure leads with cable ties.
26. Clear all leads and secure for case
wrap-around assembly.
INVERTEC V250-S
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F-76
F-76
NOTES
INVERTEC V250-S
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F-77
F-77
TROUBLESHOOTING & REPAIR
RETEST AFTER REPAIR
Should a machine under test be rejected for any reason requiring the removal of any mechanical part that could
affect the machine’s electrical characteristics, or if any electrical components are repaired or replaced, the
machine must be retested.
INPUT IDLE AMPS AND IDLE WATTS
INPUT CURRENT @ IDLE
INPUT POWER @ IDLE
LESS THAN 2 AMPS
LESS THAN 200 WATTS
MAXIMUM ACCEPTABLE OUTPUT (AT MINIMUM OUTPUT SETTINGS)
MODE
AMPS
VOLTS
All
1 Amp
10 VDC.
MINIMUM ACCEPTABLE OUTPUT (AT MAXIMUM OUTPUT SETTINGS)
MODE
AMPS
VOLTS
All
250 Amps
33 VDC.
OPEN CIRCUIT VOLTAGE RANGE
MODE
All
VOLTS
65 - 80 VDC.
INVERTEC V250-S
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F-78
F-78
NOTES
INVERTEC V250-S
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G-1
G-1
ELECTRICAL DIAGRAMS
Electrical Diagram Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section G
Wiring Diagram (Codes 10102, 10103) . . . . . . . . . . . . . . . . . . . . . . . . . . . G-2
Wiring Diagram (Codes 10187, 10188) . . . . . . . . . . . . . . . . . . . . . . . . . . . G-3
Control PC Board (G2666) Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-4
Power PC Board (G2684) Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-5
Control PC Board (G2666) Schematic. . . . . . . . . . . . . . . . . . . . . . . . . . . . G-6
Power PC Board (G2684) Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-7
INVERTEC V250-S
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NOTES
INVERTEC V250-S
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G-2
G-2
ELECTRICAL DIAGRAMS
Wiring Diagram (Codes 10102, 10103)
L2 RIGHT
D8
S
F
F
C4
R2
10
2W
204
BACK
OUTSIDE
+ ARC
- ARC
F
.001/400
BACK
AUX.
206
C5
C6
TP5
TP4
S
F
S
S
N.C.
229
204
201
205
206
C1
204
201
205
TP6
FRONT
INSIDE
1600/450
BACK
I
D5, D6, D7
-
F
S
F
S4
202
203A
203
203
206
201
203A
PRIMARY
203A
F
207
202A
202
RECONNECT
SWITCH
205
POWER
BOARD
F
S
B
315
316
W
I
FRONT
OUTSIDE
Y
Y
202A
FRONT
2
3
CC SOFT
CC GTAW
CC CRISP
S
F
304
S2
T3
CURRENT
1
303
S
MODE
SWITCH
2
1
202A
W
B
309
310
307
308
311
313
1
6
7
4
2
8
3
S
S1
POWER
OFF
C2
1600/450
BACK
INSIDE
303A
J4
FRONT
AUX.
D2, D3, D4
.001/400
TRANSFORMER
207
305
-
F
ON
F
10
2W
208
207A
208
R1
375
377
324
376
330
321
303
305
304
327
328
229
319
-
1
W
208
A
B
C
207A
F
J2
C3
U
V
H1
F
S
2
3
4
303A
330
S3
TP1
TP2
H1
REMOTE
LOCAL
1
2
3
4
5
6
308
307
310
311
313
309
D9
INPUT
BRIDGE
D1
LOCAL/REMOTE
SWITCH
L1 LEFT
Y
Y
R
INPUT
PER
N.A.
T1
MAIN
TRANSFORMER
5
5
6
7
8
9
10
11
12
13
14
J6
TP3
CW (MAX)
377
376
+
209
D
B
R3
OUTPUT
CONTROL
J3
J5
316
2
4
3
1
W
209
A
10K
2W
317
R
R
G
J1
375
375B
FAN
CONTROL
BOARD
A
A
327
328
CW (MAX)
R4
MOTORS
H1
H3
0.6 AMP
SLOW
BLOW
ARC FORCE
/INDUCTANCE
CONTROL
10K
2W
315
R6
317
4
2
5
1
6
3
J7
H1
H2
H3
H4
H5
1
4
2
3
H1
H2
H3
H4
H5
324
CW (MAX)
100
5W
R5
322 318
76 77
75
R
R
R
R
STRIKE ENERGY
CONTROL
50K
2W
200-
R
208V H3
375B
18V
220-
230V
R
380-
415V
6
5
A
440-
460V
T2
J2
J1
J5, J6, J7
J4
N.C.
J3
+
321
319
AUXILIARY
TRANSFORMER
THERMAL
OVERLOAD
INDICATOR
Y
NOTES:
N.A.
1. FOR MACHINES SUPPLIED WITH INPUT CABLE
CONNECTOR CAVITY NUMBERING SEQUENCE
(VIEWED FROM COMPONENT SIDE OF BOARD)
FOR SINGLE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
CONNECT BLACK & WHITE LEADS TO SUPPLY CIRCUIT.
WRAP RED LEAD WITH TAPE TO PROVIDE 600V. INSULATION.
322
318
75
D
E
C
GTAW (REMOTE)
TRIGGER
2
4
FOR THREE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
CONNECT BLACK, RED & WHITE LEADS TO SUPPLY CIRCUIT.
MIN
75
2. FOR MACHINES NOT SUPPLIED WITH INPUT CABLE
REMOTE
OUTPUT
CONTROL
FOR SINGLE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
CONNECT TERMINALS U & W TO SUPPLY CIRCUIT.
FOR THREE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
CONNECT TERMINALS U, V & W TO SUPPLY CIRCUIT.
76
77
76
77
B
A
COLOR CODE:
B = BLACK
G = GREEN
R = RED
W = WHITE
Y = YELLOW
F
G
GND
N.B. SINCE COMPONENTS OR CIRCUITRY OF A PRINTED CIRCUIT BOARD MAY CHANGE WITHOUT AFFECTING
THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY NOT SHOW THE EXACT
COMPONENTS OR CIRCUITRY HAVING A COMMON CODE NUMBER.
REMOTE
CONTROL
RECEPTACLE
N.C. PLACE "A" LEAD ON APPROPRIATE CONNECTION FOR INPUT VOLTAGE.
CONNECTION SHOWN IS FOR 440-460V OPERATION.
N.D. D2 THRU D4 OUTPUT DIODES ARE A MATCHED SET.
D5 THRU D7 OUTPUT DIODES ARE A MATCHED SET.
N.E. C1, C2 CAPACITORS ARE A MATCHED SET.
ELECTRICAL SYMBOLS PER E1537
8-5-94
L9280
CLEVELAND, OHIO U.S.A.
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
INVERTEC V250S
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G-3
G-3
ELECTRICAL DIAGRAMS
Wiring Diagram (Codes 10187, 10188)
L2 RIGHT
D1A
S
F
F
10
2W
204
BACK
OUTSIDE
+ ARC
- ARC
F
BACK
AUX.
206
C5
C6
TP5
TP4
S
F
S
S
N.C.
229
204
201
205
206
C1
D2B
204
201
205
TP6
FRONT
INSIDE
1600/450
BACK
I
-
F
S
F
S4
202
203A
203
203
206
201
203A
PRIMARY
203A
F
207
202A
202
RECONNECT
SWITCH
SHUNT
317
320
205
POWER
BOARD
F
S
B
W
I
FRONT
OUTSIDE
Y
Y
202A
FRONT
2
3
CC SOFT
CC GTAW
CC CRISP
S
F
304
S2
MODE
SWITCH
T3
CURRENT
TRANSFORMER
1
D2A
303
S
2
1
202A
W
B
309
310
307
308
311
313
1
6
7
4
2
8
3
S
S1
POWER
OFF
C2
1600/450
BACK
INSIDE
303A
J4
FRONT
AUX.
207
305
-
F
ON
F
10
2W
208
207A
208
375
377
324
376
330
321
303
305
304
327
328
229
319
-
1
W
207A
208
A
B
C
F
J2
U
V
F
H1
H1
S
2
3
4
303A
330
S3
TP1
TP2
REMOTE
LOCAL
1
2
3
4
5
6
308
307
310
311
313
309
D9
INPUT
BRIDGE
D1B
LOCAL/REMOTE
SWITCH
L1 LEFT
Y
Y
R
320
INPUT
PER
N.A.
T1
MAIN
TRANSFORMER
5
5
6
7
8
9
10
11
12
13
14
J6
OUTPUT
RECTIFIER
HEATSINK
TP3
CW (MAX)
377
376
+
209
D
B
R3
OUTPUT
CONTROL
J3
J5
316
2
4
3
1
W
209
A
10K
2W
318
317
R
R
G
J1
318
POWER BOARD
375
375B
HEATSINK
FAN
MOTORS
CONTROL
BOARD
A
A
327
328
CW (MAX)
316
R4
H1
0.6 AMP
SLOW
BLOW
ARC FORCE
/INDUCTANCE
CONTROL
10K
2W
H3
4
2
5
1
6
3
J7
H1
H2
H3
H4
H5
1
4
2
3
H1
H2
324
CW (MAX)
R5
322 318
76 77
75
STRIKE ENERGY
CONTROL
50K
2W
200-
R
208V H3
375B
18V
H3
H4
H5
220-
230V
R
380-
415V
6
5
A
440-
460V
T2
J2
J1
J5, J6, J7
J4
N.C.
J3
+
321
319
AUXILIARY
TRANSFORMER
THERMAL
OVERLOAD
INDICATOR
Y
NOTES:
N.A.
1. FOR MACHINES SUPPLIED WITH INPUT CABLE
CONNECTOR CAVITY NUMBERING SEQUENCE
(VIEWED FROM COMPONENT SIDE OF BOARD)
FOR SINGLE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
CONNECT BLACK & WHITE LEADS TO SUPPLY CIRCUIT.
WRAP RED LEAD WITH TAPE TO PROVIDE 600V. INSULATION.
322
318
75
D
E
C
GTAW (REMOTE)
TRIGGER
2
4
FOR THREE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
CONNECT BLACK, RED & WHITE LEADS TO SUPPLY CIRCUIT.
2. FOR MACHINES NOT SUPPLIED WITH INPUT CABLE
MIN
75
REMOTE
OUTPUT
CONTROL
FOR SINGLE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
CONNECT TERMINALS U & W TO SUPPLY CIRCUIT.
FOR THREE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
CONNECT TERMINALS U, V & W TO SUPPLY CIRCUIT.
76
77
76
77
B
A
COLOR CODE:
B = BLACK
G = GREEN
R = RED
W = WHITE
Y = YELLOW
F
G
GND
N.B. SINCE COMPONENTS OR CIRCUITRY OF A PRINTED CIRCUIT BOARD MAY CHANGE WITHOUT AFFECTING
THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY NOT SHOW THE EXACT
COMPONENTS OR CIRCUITRY HAVING A COMMON CODE NUMBER.
REMOTE
N.C. PLACE "A" LEAD ON APPROPRIATE CONNECTION FOR INPUT VOLTAGE.
CONNECTION SHOWN IS FOR 440-460V OPERATION.
CONTROL
RECEPTACLE
N.D. D2 THRU D4 OUTPUT DIODES ARE A MATCHED SET.
D5 THRU D7 OUTPUT DIODES ARE A MATCHED SET.
N.E. C1, C2 CAPACITORS ARE A MATCHED SET.
ELECTRICAL SYMBOLS PER E1537
9-29-95E
L9907
CLEVELAND, OHIO U.S.A.
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
INVERTEC V250S
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G-4
G-4
ELECTRICAL DIAGRAMS
Control PC Board (G2666) Layout
ITEM
REQ'D
IDENTIFICATION
CONTROL P.C. BOARD AS'BLY
G2666
R86
C50
X9
C51
R104
R105
R116
R117
R118
R72
R71
X8
R70
R119
D27
X7
X6
R114
R113
R115
R120
R121
R122
R111
R54
R30
R31
D26
R127
R39
Q3
R129
R130
R128
R45
C35
R60
R46
C25
D10
C24
R6
R5
X5
DZ4
C11
X4
Q1
D8
C20
C10
X3
R10
R12
D29
D7
D35
C7
R11
C6
C5
R106
R107
C4
C2
X2
R1
CAPACITORS
RESISTORS
=
=
MFD/VOLTS
OHMS
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
in danger to the Machine Operator or Technician. Improper PC board repairDsocwonuloladd rfreosmuWltwinw.Sdoammanaugaels.ctoomt.hAell MmaancuahlisnSee.arch And Download.
INVERTEC V250S
G-5
G-5
ELECTRICAL DIAGRAMS
Power PC Board (G2684) Layout
G2684
POWER P.C. BD. AS'BLY
REQ'D
IDENTIFICATION
ITEM
J6
D7
R78
C10
R61
OCI2
R50
R51
D4
X2
R56
R35
R40
D2
C7
R12
R14
R15
R37
R76
R16
C4
R19
R17
DZ4
B207A
B203A
DZ11
DZ5
R20
R25
R45
R44
R43
R42
DZ6
C8
C5
R24
R23
R22
R21
DZ10
R46
R41
B202A
B206
DZ9
DZ7
DZ14
DZ1
R66
R65
R64
R63
R1
R6
DZ2
C11
C1
R5
R4
R3
R2
DZ13
R67
R62
DZ12
DZ3
CAPACITORS = MFD/VOLTS
RESISTORS = OHMS
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
in danger to the Machine Operator or Technician. Improper PC board repairDsocwonuloladd rfreosmuWltwinw.Sdoammanaugaels.ctoomt.hAell MmaancuahlisnSee.arch And Download.
INVERTEC V250S
G-6
G-6
ELECTRICAL DIAGRAMS
Control PC Board (G2666) Schematic
2 6 6 G 5
+15V
PRECHARGE TIMER
+15V
J2
J2
+15V
1
R29
10.0
R28
10.0
+15V
R48
221
DZ12
12V
RELAY COILS
6
R9
Q3
4A
100V
1W
D
600mA
Q1
D13
D12
40V
D29
1.0A
30V
+
t
G
F
R41
R23
.24
100K
DZ3
20V
1W
S
D11
R1
1.00K
33.2K
DZ5
15V
1W
J2
C23
.1
33.2K
4
D6
D3
1
8
7
6
5
1.0
5W
V
S
VS
D2
50V
J1
1.00K
33.2K
2
3
47.5
IN
OUT
OUT
GND
D8
1.0A
30V
R7
IN
OUT
1
X2
C20
0.1
50V
X1
NC
4.75K
267
18VAC
1.50K
4
Q7
GND
LM350
C6
0.1
50V
+15V
C2
3300
50V
TO PULSE
600mA
TP1
50V
15J
J1
FROM AUXILIARY
TRANSFORMER
243
TSC4429JJA
C4
150
50V
DZ2
12V
1W
40V
2
ADJ
10
9
TRANSFORMER
100K
1.50K
8
D46
J1
3
DZ1
18V
1W
6
R34
X8
C12
.1
50V
C3
J3
C7
THERMOSTATS
+15V
D35
1.0A
30V
1
8
R65
33.2K
15.0K
2.67K
V
S
VS
10K
(+)
D1
4.7
E
D4
7
6
5
2
IN
OUT
OUT
GND
35V
R15
267
C5
X4
J1
J2
7
3
4
R67
0.1
NC
D10
J2
4
C10
Y
THERMAL
LIGHT
50V
332K
2
GND
TSC4429JJA
16
0.1
1
DZ4
12V
SET
V
DD
D7
1.0A
30V
50V
J3
R36
100K
2
3
4
5
6
7
15
14
13
12
11
RESET
MONO IN
OSC INH
47.5
13
1W
X5
FROM
332K
IN
1
PROTECTION
CIRCUIT
C21
.0047
50V
OUT
OUT
1
DECODE
t
o
R5
D23
D32
56
2
D
C
B
+15V
J2
8
R35
47.5K
8
BY-PASS
J5
10
CLOCK INH
VSS
13
12
D45
DZ8
X6
8
9
D22
75V
A
1
D5
1W
4536B
R2
332K
R3
Q4
500mA
300V
100K
100K
11
10
C49
.1
50V
C1
.1
50V
2
4
X6
R49
10K
crisp
J2
J2
TRIGGER
INTERFACE
3
5
+IFB
FEEDBACK
CURRENT
D17
1N4936
C22
.022
50V
2700p
50V
C24
.15
+15V
D14
-IFB
R33
4
1
1/2W
SHUNT
AMPLIFIER
100V
D18
1N4936
2.21K
C44
R91
J5
TEST PT
Vi
D
PRIMARY
CURRENT
FEEDBACK
26.7
26.7
R22
221
o
56.2K
t
D9
D15
1N4936
J4
13
12
1.50K
R6
56
-
C19
2700p
50V
1
R89
332
R27
26.7
R25
26.7
14
SHUNT
J4
2.94K
X9
TEST PT
B
+
2
R104
100
R90
D16
1N4936
2.94K
C51
.1
50V
C33
C43
2700p
50V
56.2K
Vref
.022
C18
1.8
20V
50
V
Test Pt
A
18.2K
2
3
O.C.V.
Vi
R105
10K
R69
C42
.1
50V
1
47.5K
X9
HOLD DOWN
100K
R19
10K
13
Vref
Q2
600mA
40V
14
D31
X8
R56
X3
1
16
15
14
13
12
11
12
+15V
Vref
SHUT
Vin
C17
1.8
20V
CLIM
100K
R84
OPEN
2
Vref
10K
47.5K
33.2K
C27
4.7
35V
CIRCUIT
STICK
3
C41
.1
50V
C9
4.7
35V
C39
.022
50V
I-
OUTB
Vc
2.21K
+15V
D21
2.21K
4
DETECTOR
26.7K
J3
STARTING
I+
5
V+
GND
OUTA
SYNC
RT
6
V-
7
10
J3
3
COMP
R39
12
R30
562
R116
562
R31
R32
562
R110
562
R119
562
R111
562
R120
562
R112
8
9
MAX
CW
CT
1.50K
C45
47p
100V
+
ARC
SG3847
+15V
562
R117
562
562
R121
562
56.2K
22.1K
STRIKE
CONTROL
R118
562
75VDC
OCV
50K
D30
PWM
CONTROL
Q6
8.25K
8.25K
R78
R87
600mA
40V
C14
150p
50V
R122
562
R123
562
R124
562
R125
562
R126
562
R127
562
C15
.022
50V
3.32K
100K
C25
100
20V
C11
.018
50V
Vref
D28
SHORTING
DETECTOR
D20
9
9
10K
CW
D27
J3
J3
8
8
X7
D
10
11
R57
R70
X9
10
DZ9
10V
1W
C26
.0047
50V
6.19K
1.50K
3.32K
C30
.1
50V
6
3
R75
R62
4.75K
D33
1N914
15.0K
X6
R58
4.75K
crisp
soft
C29
.022
50V
ARC FORCE
C36
.022
50V
TEST PT
E
R74
82.5K
47.5K
47.5K
4
SD'
R73
10K
C16
47p
100V
Vref
D19
D37
6.81K
R47
12
crisp
R113
R81
47.5
soft
X7
C
D38
1.00K
DZ7
6.2V
1W
J3
R52
11
10
332K
2.21K
2
Vi
OVERCURRENT
FOLDBACK
+15V
100K
CW
MAX
D42
D26
6
D40
1N914
J3
J3
DZ11
D41
OUTPUT
CONTROL
4
R114
7
X7
5.1V
2
1
X8
C47
1W
10K
47.5
C28
.022
50V
5
4.7
13
35V
R85
Vref
100K
1
R115
Vref
C46
150p
100V
6.19K
Vi
47.5
6
5
R109
332K
R93
33.2K
J5
7
R96
R99
X9
R94
33.2K
3
D36
332K
1.50K
C48
o
R92
10K
t
R46
56
47.5K
1.0
DZ10
5.1V
1W
35V
10K
CURRENT
CONTROL
LOCAL
J3
1
2
5
X6
AMPLIFIER
C40
.022
50V
C38
.022
50V
R103
332K
10K
MODE SWITCH
REMOTE
4.75K
SPDT-Center off
Vi
soft
47.5K
R64
R101
J3
2
3
2
Q5
9
100K
X8
600mA
40V
1
Vref
D24
J3
J3
R98
7
R86
100
TIG
10K
+15V
100K
1
+15V
crisp
crisp
13.7K
8
R59
3
FILENAME: G2665_1CB
D44
D43
10K
14
4
4
5
6
14
16
X6
X6
SD'
GENERAL INFORMATION
ELECTRICAL SYMBOLS PER E1537
LAST NO. USED
SOFT SCRATCH
C32
.022
50V
R- 130
C- 51
D- 46
Q-
X-
7
C50
.022
50V
C31
.022
50V
C13
.022
50V
X9
X7
X8
X5
X6
9
C8
.022
50V
CAPACITORS
RESISTORS
DIODES
=
MFD
(
.022/50V
1/4W
UNLESS OTHERWISE SPECIFIED)
UNLESS OTHERWISE SPECIFIED)
+15V
J5
4066B
7
HEXTRGR
LT1014
11
DZ- 12
LM224
11
LABELS
=
Ohms
(
9
8
77
5
4536B
8
=
1A, 400V
(UNLESS OTHERWISE SPECIFIED)
o
SUPPLY
VOLTAGE NET
t
7
R45
56
POWER SUPPLY SOURCE POINT
COMMON CONNECTION
75
76
5
D39
D34
J5
6
X7
4
3
FRAME CONNECTION
o
C35
t
.1
EARTH GROUND CONNECTION
R60
56
50V
NOTES
:
EQUIP.
TYPE
Ch'ge.Sht.No.
N.A. SINCE COMPONENTS OR CIRCUITRY ON
A
PRINTED CIRCUIT BOARD MAY CHANGE
UNLESS OTHERWISE SPECIFIED TOLERANCE
ON HOLES SIZES PER E-2056
V250S CONTROL
SCHEMATIC
THE LINCOLN ELECTRIC CO.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF COMPLETE BOARD, THIS DIAGRAM MAY
A
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING
NUMBER.
A
COMMON CODE
ON
ON
2
3
PLACE DECIMALS IS
PLACE DECIMALS IS
+
+
.O2
.OO2
SUBJECT
CLEVELAND, OHIO U.S.A.
SCALE
ON ALL ANGLES IS
+
.5 OF
A
DEGREE
SHT.
MATERIAL TOLERANCE ("t") TO AGREE
WITH PUBLISHED STANDARDS
G 2665
CHK.
SUP'S'D'G.
DR.
DATE
NO.
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
INVERTEC V250S
in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
Download from Www.Somanuals.com. All Manuals Search And Download.
G-7
G-7
ELECTRICAL DIAGRAMS
Power PC Board (G2684) Schematic
+15V
4
(RELAY DRIVE)
FROM CONTROL BD.
C3
J6
6
X2
12
LM224
14
X2
11
INPUT RECTIFIER
POSITIVE
209
2
13
CR1
D7
1
RECONNECT
206
CR1
3
4
6
J6
3
R13
R14
R15
150K
150K
150K
R10
R11
CR1
5
10W
100
10W
100
CAPACITOR
PRECHARGE
D
150K
R1
100
10W
2
10.0
DZ1
D
R17
100
R18
5
1
A1
R8
5W
6.2V
1W
3
G
1.82K
R6
2.7
OCI1
CNY17-3V
Q1
4A
900V
APT6035N
S
DZ4
12V
1W
10.0
DZ2
15V
1W
D8
1A
2.7
5W
4
6
2
1
1.00K
1.00K
1.00K
1.00K
1000V
C1
DZ3
.0047
50V
C4
.022
50V
C2
.0047
1000V
15V
1W
267K
205
5
C
TRANSFORMER
PRIMARY
BYT12P600
+15V
R29
R30
A1
2500
5W
2500
5W
A
4
2500
5W
150K
150K
BLEEDER
RESISTORS
7
C
15.0K
FILTER
CAPACITOR
325VDC
(NOMINAL)
D2
BYT12P600
2500
5W
R40
332K
+15V
A1
5
6
A
6
7
X2
C
R20
10.0
2.8K
208
TRANSFORMER
PRIMARY
9
D3
+
1
C6
D
C7
27
35V
DZ5
X1
8
.0047
A1
6.2V
1W
6.19K
10
1000V
REF
TL431
-
G
R25
10.0
6
APT6035N
S
R27
DZ6
15V
1W
562
D9
1A
16.5K
5W
2.7
8
C5
1.00K
1.00K
1.00K
1.00K
.0047
1000V
50V
2.7
5W
DZ7
5
15V
1W
G1
GATE
S1
T1
8
3
203A
RECONNECT
G2
J6
J6
GATE
1
1
S2
10
4
DRIVE
S3
GATE
G3
2
12
202A
RECONNECT
10.0
R41
9
6
B
2
FROM
CONTROL
BOARD
S4
GATE
G4
D
R48
2.7 5W
7
A2
6.2V
1W
3
G
R46
10.0
APT6035N
S
(PWM DRIVE)
2.7
5W
DZ10
15V
1W
DZ9
D10
1A
1000V
1
C8
1.00K
1.00K
1.00K
1.00K
.0047
50V
DZ11
C9
.0047
1000V
15V
1W
+15V
OVERVOLTAGE
PROTECTION
204
TRANSFORMER
PRIMARY
+15V
10K
5
C
R53
R56
332K
BLEEDER
RESISTORS
BYT12P600
R71
2500
5W
10
16.5K
3
2
8
6.19K
X2
1
9
2500
5W
X2
A2
1.82K
J6
D5
A
4
R51
4
R78
475
3.32K
150K
7
C
FILTER
CAPACITOR
1
5
D4
325VDC
(NOMINAL)
15.0K
BYT12P600
150K
OCI2
10K
CNY17-3V
TO CONTROL BD.
2500
5W
2
6
4
(VOLTAGE PROTECTION)
A2
A
6
201
A
R62
10.0
9
C12
.0047
1000V
C10
.022
50V
TRANSFORMER
2500
5W
681K
D
DZ12
PRIMARY
A2
6.2V
1W
10
J6
G
R67
R69
5
APT6035N
S
10.0
2.7 5W
DZ13
15V
1W
D11
1A
C11
.0047
50V
E
8
1.00K
1.00K
1.00K
1.00K
1000V
1.82K
DZ15
15V
1W
2.7
5W
DZ14
15V
1W
NOTE: 202,203,206,&207 BOLT ON WITH FILTER CAPS
207A
NEGATIVE
INPUT RECTIFIER
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
INVERTEC V250S
in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
Download from Www.Somanuals.com. All Manuals Search And Download.
|