# Frontier Chinese Diesel Generator Low Output



## Doug Johnson (Aug 30, 2017)

I have a Frontier 7500 diesel generator that has very low output (like 25 volts). The initial problem was no voltage output at all. I flashed the exciter field with 12 volts and got this output. I have replaced the brushes and the AVR, and it still doesn't put out any more voltage. It also has no 12 volt DC output at the panel. Voltage measurements with the AVR disconnected are as follows: Across brushes, approx 50 volts AC. L1-L2, R1-R2, and L1-R1 all read approx 8 volts AC. Any advice as to what I can do next?


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## Osviur (Sep 7, 2015)

Hi,

50 volts across the brushes is not correct, unless a rectifier be included in the rotor.

Normally there is a coil in the stator that generates an excitation voltage which is RECTIFIED, sent to the AVR, regulated and sent to the rotating field via the brushes,
so you should read DC volts at the brushes.
The rectifying process is made using a diode bridge (four diodes in a pack). I think that this bridge is not functioning correctly. 

An electric diagram would very helpful.


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