Murphy Switch OS 77R User Manual

OS77R-OS.PM5  
Model OS-77R  
Model OS-77R-I  
EFFECTIVE: 12/93  
®
Overspeed Speed Switch With Relay Output  
GENERAL INFORMATION AND MOUNTING DIRECTIONS  
SETTING THE MODEL OS77R SERIES  
IMPORTANT: The the following instructions as-  
sume terminal number 5 is grounded. Please refer to  
wiring and mounting information before attempting to ad-  
just the unit. These steps must be done before the fine  
tuning can be accomplished. The following steps should  
WARNING  
BEFORE BEGINNING INSTALLATION OF THIS MURPHY PRODUCT  
be followed for first time setup of unit.  
A. Turn “OVERSPEED ADJ.” fully clockwise.  
B. Remove the wire from terminal # 2 of the OS77R.  
C. Start engine and run at the highest RPM desired.  
Disconnect all electrical power to the machine.  
Make sure the machine cannot operate during installation.  
This is the RPM at which the engine should be  
shut down if exceeded.  
D. Connect a Voltmeter (or test light) between Termi-  
nal #1 (positive +) and Terminal # 2 (negative -) of  
the OS77R. You should read “no voltage” (test  
lamp will be OFF.)  
E. Slowly turn “OVERSPEED ADJ.” counter-clockwise  
and STOP the INSTANT battery voltage is indi-  
cated on the voltmeter (or the test light comes ON.)  
F. Slowly turn “OVERSPEED ADJ.” clockwise about  
1/8 of an inch. Now, tighten the locknut on the  
“OVERSPEED ADJ.” without disturbing the setting.  
G. Re-connect the wire to Terminal #2 on the OS77R.  
This reconnects the OVERSPEED shutdown cir-  
cuitry.  
Follow all safety warnings of the machine manufacturer.  
Read and follow all installation instructions.  
Installation Accessories  
Hardware, tools, and optional equipment needed to in-  
stall the model OS77R.  
Tools as needed for the system mounting, such as  
drill and screw driver.  
18 ga. wire for extension and hook up.  
Set of wire terminating tools.  
Wire termination; such as ring or spade terminals.  
DESCRIPTION  
The OS77R is an Overspeed Shutdown Switch used  
for protecting the engine from excessive operating speeds.  
The unit monitors a frequency generated from a magnetic  
pickup. The OS77R-I functions identically to the OS77R  
but monitors engine speed from a distributor ignition.  
If the unit senses an engine speed higher than the ad-  
justable set point, the unit will cause the engine to shut  
down.  
NOTE: If further adjustment is needed;  
Turning the “OVERSPEED ADJ.” clockwise,  
RAISES the shutdown point. This allows the en-  
gine to run at a HIGHER RPM.  
Turning the “OVERSPEED ADJ.” counter-clock-  
wise LOWERS the shutdown point. This will shut  
down the engine at a LOWER RPM.  
WARNING: Perform the mounting operation with  
power source off. The OS77R module is de-  
signed to be mounted in a flat panel. First, drill  
the mounting holes as shown on the template  
included with the packing. Insert the module from  
the back side of the panel and install mounting  
hardware.  
NOTE: Relay contacts are between terminals 2 and 5.  
Download from Www.Somanuals.com. All Manuals Search And Download.  

Miele Clothes Dryer T8002 User Manual
Miele Dishwasher G 1XXX User Manual
MTD Snow Blower E740 User Manual
Multiquip Portable Generator CDA45SSIU3 User Manual
NEC Car Video System 46 V462 TM User Manual
Nortel Networks Network Router NN47230 301 User Manual
Oki Computer Hardware 70049601 User Manual
Oki Printer 410d User Manual
Optoma Technology Home Theater System EP761 User Manual
Panasonic Drill EY6450 User Manual