TT-916: AC Phase Sensitivity

Models Affected: All Operator Aboard Extractors

Extractor Motor Runs but All Functions Move Slowly (If at All) and Pump Creates Little to No Pressure


The extractor motor is phase sensitive and will run in reverse if wired out of phase. With the motor running in reverse, the pump also runs in reverse creating little to no pressure. If ran for an extended period of time in the reverse direction, irreparable damage to the pump will occur.


To verify if the motor is running in reverse, remove the access plate on the pump-to-motor adapter and check the coupling rotation against the correct rotation indicator marked on the adapter. To correct phase reversal, switch two of the three hot leads to the motor. Refer to Technical Procedure TP-614 for complete phase correction procedures.

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