AC SENS LOST
UnclassifiedCooling
What This Code Means
AC Sensing Lost; Accessory Power Overload; High generator current detected; Generator set shuts down to protect the alternator from damage caused by overheating the windings; RXT interface connection is lost; Transfer switch phase rotation does not match; ATS will not transfer; Optional customer-connected input is closed; Battery charger fault; Engine starting battery voltage rises above 125% of the battery voltage setting for more than 10 seconds; Engine starting battery voltage falls below the battery voltage setting (typically 12.5 volts) for more than 90 seconds when the engine is not running
Possible Causes
- •Generator output AC sensing is lost
- •Over current fault (short circuit) on the accessory controller power output
- •High generator current
- •RXT interface connection is lost
- •Transfer switch phase rotation does not match
- •Optional customer-connected input is closed (Digital input from optional PIM.)
- •Input to PIM from an external battery charger (not the built-in battery charger)
- •High engine starting battery voltage
- •Low engine starting battery voltage
Suggested Actions
- 1Contact an authorized distributor/dealer for service
- 2Reduce the load
- 3Check communication wiring between transfer switch interface board and generator set
- 4Correct the ATS connection
- 5Refer to the ATS Installation manual, wiring diagrams, and labels on the transfer switch
- 6Check customer-supplied equipment
- 7Check external battery charger
- 8Check the battery rating and condition
- 9Check the battery charger operation
Related Rehlko Fault Codes
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