THOMSON TS 880 - Page 48

TS 880 TRANSFER SWITCH
PM064 REV8 10/01/25 42 Thomson Technology
Symptom Possible Causes
- Defective TSC 800 controller (verify output signals with circuit
board mounted diagnostic LED’s)
- TSC 800 has “Transfer Fail” alarm activated. Determine
cause of alarm and rectify before TSC 800 is reset
Will not transfer to generator source
upon failure of utility source
- Isolation plug out
- Generator set not producing enough voltage/frequency or
output circuit breaker is open
- TSC 800 has incorrect voltage programmed for system
voltage
- Warmup time delay function has not timed out yet (verify TSC
800 timer setting)
- A loose control connection
- Faulty motor limit switch
- Defective motor
- Defective TSC 800 controller (verify output signals with circuit
board mounted diagnostic LED’s)
- TSC 800 has “Transfer Fail” alarm activated Determine cause
of alarm and rectify before TSC 800 is reset
Transfer to generator source without a
power failure in the utility source
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-
A test mode has been activated (check TSC 800 controller)
Utility supply voltage is slightly below voltage sensing
setpoints.
Verify TSC 800 has incorrect voltage program setting for
system voltage
- Defective TSC 800 controller (verify output signals with circuit
board mounted diagnostic LED’s)
- Utility power switching device has tripped due to an over
current condition and TSC 800 “Transfer Fail” alarm activated.
Determine cause of alarm and rectify before TSC 800 is reset.
Generator does not start up or stop
when it should
- Verify remote engine control panel is set for automatic mode
No time delay when there should be
- Verify time delay function in the TSC 800 program setting as
per programming sheets as supplied with the transfer switch
Power is not available at the load
terminals but the utility or generator
power switching device appears to be
closed to a live source
- The power switching device's over current protection unit has
opened due to a fault on the system. Correct the fault, and
manually reset the power switching device in the transfer
switch by moving it off and then on again with the manual
operating handle
- Limit switch incorrectly adjusted
The transfer switch has completed a
transfer, but the motor has overheated
and the internal thermal protector has
opened
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-
Limit switch failure or improper adjustment has failed to
disconnect motor
Binding or jamming of the transfer mechanism