Generator question - no power


Looking for generator repair advice... I have a Winco 900-watt Tri-Fuel generator with about 320 hours on it for home standby use. It's worked well for years - it easily powers everything in the house except the central AC. During a power outage last night, after it had been running for about five hours, I turned on the basement light switch, the lights flashed momentarily and then went out. The only other load in the basement is a dehumidifier that I always keep running when on generator power as it helps stabilize the output. I then found that the breaker for the basement had tripped. We've been in the house over 20 years and I've never seen that breaker trip. I reset the breaker and then the entire house went dark. The generator kept right on running with no noticeable change in sound (i.e. it didn't sound like it was working harder or easing up). I tried resetting the breakers on the generator, plugged a light into the outlets on the generator panel - but nothing worked. I turned it off for a while to see if maybe the problem was heat-related. Still no luck. It starts up just fine but produces no power. It seems unlikely that the problem would be a loss of residual magnetism. It gets exercised regularly, and it was running for five hours when it failed. Does anyone have any suggestions for things to look for?
btw: After the main power came on, I turned on the breaker for the basement and everything functioned normally.
tia
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alt.energy.homepower is where alot use and know generators
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Nick Danger wrote:

Sounds like the utility power came on and fried your generator. Did you have the MAINS off?
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The generator is connected through a transfer switch - installed by licensed electricians with town permit, inspection, etc. It is physically impossible for mains power and generator power to get into the house wiring at the same time. The mains power didn't come back on until 1.5 hours after the generator died.
Also - I had a typo in my original post. The generator is 9000 watts, not 900.
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do the makers of your generator have a website,and does it have any service data,FAQ,or other useful info?
--
Jim Yanik
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Not much comes to mind. Plug something else into the generator, and see if the genset is putting out power.
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Christopher A. Young
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Did you try plugging something directly into the unit or take a meter and try to trace power, it could be simple like a wire came loose, are generetor brushes ok.
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