FW Murphy Selectronic S1501 series, Installation And Operation Manual

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Section 50 00-02-0271
2018-10-23 - 25 -
Troubleshooting
WARNING:
Do NOT open power supply until operations have been
shut down and area has been rendered non-hazardous. Do NOT run
sensor wires in conduit with any other wire. Do NOT apply voltage
to any annunciator input terminals. Do NOT bundle sensor wires
with any other wiring. Make sure the voltage and current
requirements are within the S1501 system ratings.
Before going through the checklist below, refer to the connections and operation procedures.
Also check your system wiring schematic.
If any problems persist after you have made these checks, consult your nearest Murphy
facility.
Symptom: No display

Check that the Power & Control cable is firmly connected to the back of the S1501.
Check for damaged or broken wire.

Check for power failure or power input shutdown.

Check the 200 mA fuse within the S1501 power supply and replace if necessary.
NOTE: If after all of the above has been done, and there is still no display,
return the S1501 to Murphy for repair or replacement.
Symptom: Engine fails to start (Sensor switch fault display cannot be
cleared.)

Check that the Power & Control cable is firmly connected to the back of the S1501.
Check for damaged or broken wire.

Check that the sensor input cable connector (ribbon cable) is properly connected to
the back of the S1501.

Verify that the LED lights (within the power supply box) are lit indicating relays are
functioning.

Check that the wire leads on the terminal block under the Safety Barrier cover are
connected and tight. (See drawing at right.)

Measure the voltage between terminals 1 and 2 on the terminal block under the
Safety Barrier cover (voltage should read between 5 - 6 VDC). Do this with the
S1501 connected to the power supply, and with it disconnected. There should not be
more than a 0.5 V difference between the readings with the S1501 connected and
not connected.