Troubleshooting
14| Symptom | Cause | Remedy |
|---|---|---|
| Interlock(s) misaligned | Interlock(s) misaligned | Realign interlock(s). |
| Interlock(s) damaged | Interlock(s) damaged | Replace interlock(s). |
| Contactor defective | Contactor defective | Replace contactor. |
| Contactor interlock shaft defective | Contactor interlock shaft defective | Replace contactor. |
| Mechanical interlock interference | ||
| Contactor’s mechanical latch defective | Check/fix mechanical interlo | |
| A magnetically held (145-400 ampere) contactor fails to hold a closed setting | Check/fix mechanical interlock. | |
| A magnetically held (145-400 ampere) contactor fails to manually open or close | Check/fix mechanical interlock. | |
| Manual operator damaged | Check/fix mechanical interlock. | |
| Transfer switch will not transfer back to normal. | Check for rated switch voltage at terminals NA and NC of the transformer assembly. Is the voltage correct? Is there between 24 and 26 vac between terminal T2 and terminal T3 of the transformer assembly? | Adjust normal voltage setpoint. See Main Circuit Board Voltage Adjustments, Normal Source in Section 3. Check the wiring harness from transformers to the power switching device for an open circuit. Repair or replace wiring harness from the transformer to the logic board. |
| Transfer switch will not transfer to emergency. | Is the voltage at the emergency transformers correct? Does the ER relay (K2) pull in? Does the ATS disconnect the load from the normal source? | A10: Disconnect plugs P8 and P9 from the interface relay board. Is the voltage between pins P8-6 to P9-6, 25.5 to 26.5 vac? A11: Is there any damage to the interface relay board (burn traces, resistors, etc.)? A12: Is the TDOE relay functioning? |
| Transfer switch will not transfer to normal. | Is the voltage at the emergency transformers correct? Does the NR relay (K1) pull in? Does the ATS disconnect the load from the emergency source? | B10: Disconnect plugs P8 and P9 from the interface relay board. Is the voltage between pins P8-7 to P9-7, 25.5 to 26.5 vac? B11: Is there any damage to the interface relay board (burn traces, resistors, etc.)? B12: Is the TDON relay functioning properly? |
| Accidental starting | Disconnect battery cables before working on generator set (negative lead first and reconnect it last). Turn generator set master switch to OFF position, disconnect power to battery charger, and remove battery cables (remove negative lead first and reconnect it last) to disable generator set before working on any equipment connected to generator set. | |
| The ohmmeter will show infinite resistance. | Turn pot R17 slowly clockwise until the ohmmeter shows no resistance. |
Symptom → cause → remedy extracted from this unit’s service/owner documentation; verify against the official manual before servicing.
About
Kohler TES — transfer switch. Specifications and parts compiled from manufacturer documents.