How to "flash" a generator when output is lost due to loss of excitation

Residual magnetism in the generator exciter field allows the generator to build up voltage during start-up. This magnetism is sometimes lost due to shelf time or improper operation, among other reasons. Restoring this residual magnetism is possible and is sometimes referred to as

"flashing the exciter field".

To restore the small amount of residual magnetism necessary to begin voltage buildup, connect a 12 volt battery to the exciter field while the generator is NOT ROTATING, as follows:

  1. Connect White lead of generator to the positive pole of the battery.

  2. Hold the Black lead of generator by the insulated portion of the lead wire, touch Black lead to the negative pole of the battery for a few seconds, then remove.

  3. Repeat the procedure if the generator fails to build voltage. 


Note: Self excited generators with receptacles will require a short pig tail with plug.


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