Forum Discussion
42 Replies
- SHREDExplorer
dougrainer wrote:
I never had brushes or rings cause an EXCESS of voltage. Usually low or no voltage. I HAVE had Voltage regulators fail on those older Onan's. Doug
PS. the ONLY thing that ever caused excess voltage was the Running speed of the genset. Never had the Voltage regulator cause extreme high voltage. Also, if your model Onan fails to produce 120, the genset shuts down.
I apologize for not being clearer.
In fairness the tech never claimed the brushes and rings caused the spike but rather most likely contributed to regulator damage (which has yet to be determined but likely). - I never had brushes or rings cause an EXCESS of voltage. Usually low or no voltage. I HAVE had Voltage regulators fail on those older Onan's. Doug
PS. the ONLY thing that ever caused excess voltage was the Running speed of the genset. Never had the Voltage regulator cause extreme high voltage. Also, if your model Onan fails to produce 120, the genset shuts down. - SHREDExplorer
MEXICOWANDERER wrote:
Hint: Use only FLINT PAPER on slip rings. Other materials embed abrasive particles in the copper wildly accelerating graphite brush deterioration. Brush contact to chassis ground resistance should not affect a 30 megohm reading. Disconnected from load the same is true for stator lead tests.
The Flight Systems tech pointed me to the brushes and rings for the ohm reading and voltage issues. That's why I am focused there. He said that the Onan voltage regulators do not like fluctuations and it very well could be damaged.
Anyway, I'm just passing along what he said. - SHREDExplorer
enblethen wrote:
Fight Systems sends a tool to clean slip rings
I ordered it.
It'll be here Friday. - Fight Systems sends a tool to clean slip rings
- MEXICOWANDERERExplorerHint: Use only FLINT PAPER on slip rings. Other materials embed abrasive particles in the copper wildly accelerating graphite brush deterioration. Brush contact to chassis ground resistance should not affect a 30 megohm reading. Disconnected from load the same is true for stator lead tests.
- SHREDExplorerUPDATE
I followed this video for testing.
MEASURING YOUR GENERATOR WINDINGS
I then called Flight Systems with the results.
They are so helpful.
Pins 9 and 10 test was not good.
I've got new brushes and springs coming plus I need to shine up the rings.
Chances are my regulator is damaged they said by the fluctuations from the brushes not making good contact.
That video is very helpful. - Light bulbs with tungsten filaments are a thing of the past.
Nasty when high voltages popped them and broke the glass.
What did work but hard to find is neon light bulbs. - poppaExplorer
3 tons wrote:
what? no light bulb for a meter? maybe a true rms meter?
Note that 170v is standard AC sinusoidal ‘peak’ voltage that relates to 120v which is RMS... Perhaps check your instrument settings...
3 tons - Flight Systems was easy to work with!
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