27KW Genset has slight flicker with incandescent lamps

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Genitup
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glad to find your site, hard to find forums for generators for some reason…

So I have approximately 10-year-old Generac 27KW liquid cooled running on natural model 0056390 that is generally running well except one thing, and that is when driving incandescent or LED lamps (no dimmers involved) there is a very subtle flicker in light output (and therefore power being delivered to that lamp I assume).
Engine is running smoothly and uniformly.
I checked the voltage and its seems pretty stable at 118V fluctuating maybe .5V, I also checked the frequency output and it seems stable fluctuating between 59.7 and 60 Hz. I checked the current on each leg and one was running at 8 A and one was running at 12 A, and although this is a pretty big percent difference between the two I would think with this small of a load that would'nt be an issue..

so now for my question, is this normal operation or is this some part starting to fail?
I don't remember it doing this in the past, (although it may have, I haven't had to use it for some time) but like I say it's rather subtle but noticeable and somewhat annoying.

Thanks in advance, James.
Chris
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The voltage regulator in that unit has 3 pots which can be adjusted to help the flicker. I don't have the procedure handy right this minute, but I will see if I can track it down!

Involves loading the gen and adjusting using a GOOD quality digital meter to monitor voltage.
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Genitup
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Thanks Chris!
Chris
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This is the adjustment procedure for the 0G2885A/0G28850SRV voltage regulators. Please note step 6!
0G2885A Adjustment.PNG
0G2885A Adjustment.PNG (78.58 KiB) Viewed 461 times
Generac tech for over 12 years. I'm here to help!
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Genitup
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thanks for this Chris,
I notice that there is an A or SRV suffix to the 0G2885 part number and it makes me wonder if there isn't some later revision to the regulator I have without suffixes?
I will do the procedure in the next day or so and report then.
Chris
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There is a newer version than what you have. It's seen here: https://shop.gentekpower.com/products/g ... ulator-avr
Generac tech for over 12 years. I'm here to help!
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Genitup
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any idea what the problem with the original version was and why they would have revised it ?
Chris
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That I don't know to be honest. They revise electronic parts all the time though with the 0SRV endings. It's basically the final version to replace older part numbers, and then they issue new Revision numbers along the way with the new part number.
Generac tech for over 12 years. I'm here to help!
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Genitup
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okay, so did the voltage regulator adjustment and that went smooth, set the voltage to 240 V, unloaded then when small 10 amp load is applied voltage drops to about 237.5v, does this sound about right or should it be much closer to 240 volts??
Flickr is still there however…
by the way adjustment pots got set almost exactly where they were before..
any ideas?
Chris
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You need more than 10 amps. That gen is good for over 100A. I would load it at least 50% and see how it reacts then. Use electric ovens, stove, whatever to put some real load on it!
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