Contactor open

Alarm Description: 
Main contactor remains open

The Main Contactor coil is activated in order to close the Main Contactor, but the Main Contactor does not close.  This is determined by measuring the voltage on the capacitor bank of the controller.  If this voltage does not increase, it is determined that the Main Contactor has not successfully closed.  Possible causes are:

  1. 1. The Main Contactor's coil is damaged and not creating a large enough EMF to close the Main Contactor's bolt.
  2. 2. The contacts of the Main Contactor are damaged (ie. pitted), which does not allow for it to fully close.
  3. 3. The power cable from the Main Contactor to the +battery connection of the controller is interrupted.
Associated Products: 


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