THOMSON TS 880 - Performance Test; 15 Troubleshooting (100 A-1200 A Molded Case Switch Type Ats)

TS 880 TRANSFER SWITCH
PM064 REV8 10/01/25 40 Thomson Technology
14.1. PERFORMANCE TEST
Qualified Field Service technicians require a calibrated current injection test apparatus and
must be knowledgeable in power switching unit testing to provide primary neutral CT
injection up to or greater than the trip setpoint as selected by the responsible party. As
indicated in the NEC, the maximum setting of the ground fault protection shall be 1200
amps, and the maximum time delay shall be 1 second for ground faults equal to or greater
than 3000 amps.
The inspection authority should be contacted to confirm actual test requirements as these
may vary by region or local code requirements.
The interconnected system shall be evaluated to ensure compliance with the appropriate
schematic drawings. The proper location of sensors and power cabling shall be
determined. The grounding points of the system shall be verified to determine that ground
paths do not exist that would bypass the sensors. The use of high-voltage testers and
resistance bridges may be required. A simulated fault current is to be generated by a coil
around the sensors. The reaction of the circuit-interrupting device is to be observed for
correct response. The results of the test are to be recorded on the test form provided.
15. TROUBLESHOOTING (100A-1200A MOLDED CASE SWITCH TYPE
ATS)
CAUTION!!!
All troubleshooting/service work performed must be done by qualified
personnel only. Failure to do so may cause personal injury or death.
Symptom Possible Causes
Will not re-transfer to utility source
upon restoration
- Isolation plug out
- Utility disconnect switch is in the de-energized position
(Service Entrance Rated ATS). Switch to the Energized
position.
- A test mode has been activated (check TSC 800 controller)
- Utility voltage is below the pre-programmed limits (check utility
source for adequate voltage)
- A loose control connection
- Faulty motor limit switch
- Defective motor
- TSC 800 has incorrect voltage programmed for correct system
voltage