Thermo Electron 8600 Series, Troubleshooting Service Manual

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2.10 Symptom: High Stage System Failure Alarm (continued)
Order Possible Cause Verification Action
5
Restriction in high stage capillary
tube. Measure the temperature at the heat exchanger.
If a restriction exists, the heat exchanger will be
warmer than normal. Recondition high stage.
2.11 Symptom: Power Failure Alarm
Order Possible Cause Verification Action
1
Unplugged line cord.
Check that line cord is properly seated in wall
connection and relay enclosure. Re-attach line cord and install strain relief per
user’s manual, if required.
Verify switch / circuit breaker (power switch) by
continuity or test for line voltage on high voltage
board where wires from switch are connected to
board.
Replace if required.
2
Unit circuit breaker (power switch).
Verify switch / circuit breaker does not trip below
amperage rating. Replace if required.
If trips above rating, go to step 5.
3
Loose wires
Circuit Breaker/ Power switch.
High voltage board.
Switching power supply.
Verify line voltage connection from circuit
breaker/power switch to high voltage board inputs
and ribbon cable connection from high voltage
board to DC switching power supply. Seat or replace as required.
4
Defective switching power supply.
Verify input line voltage and output voltage,
+14 VDC, is present at switching power supply. Replace if required.
5
Damaged components or wiring. Inspect relay enclosure for damaged components
and wiring. Replace as required.
6
Defective starting hardware or
compressor(s).
Check both stages for L.R.A.
If compressor attempts to run and draws L.R.A.,
check start relay for proper operation and values on
start and run capacitors. Ohm compressor windings
and compare to nominal values (Appendix B).
Dedicated circuit and correct rating? Advise customer.
7
Facility Wiring
Circuit breaker
Wire.
Connections, gauge size, and length. Try a different circuit. Fix as required.