Generac 22kw voltage too high?

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Dieseldan73
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Hello, brand new member here. Been an electrician for 22 years and started installing residential backup generators about 10 years ago. Just finished one up this morning and while checking the voltages, they are higher then I usually see with the Generacs. Phase to phase is 260 volts and A phase to neutral is 131 volts and B to neutral is 128 volts. All the others I've installed over the years have been 246 volts max phase to phase. Is there an issue with this one, or is this still acceptable? It is a brand new 22kw Generac that I just got delivered after ordering it in September. Is the voltage regulator adjustable on these units. The utility voltage is 246 volts phase to phase and 123 phase to neutral. Any help would be appreciated.
Chris
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That's too high!

I would get a dealer involved to check it over and see what's going on. I've never had to adjust the voltage output on one from the factory. You may also want to confirm with another known good meter...
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grsthegreat
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you can adjust output voltage thru the dealer menu, but its not finite. i agree on checking with another meter and on the dealer access panel also. if you overadjust the setting you can damage generator.

i cant believe it left the factory not adjusted right.
Dieseldan73
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Well, I went to another job later in the day and used my meter again and got a lot of off the wall readings again. I ended up changing the batteries and then they were normal. Went back to the generator job and retested and its ok. 120, 121 volts phase to neutral and 243 volts phase to phase. Never had the tested do that when the batteries were low. Thanks guys. Glad I found this forum. I'm sure I'll have more questions
Birken Vogt
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I have had several off brand meters give high voltage readings when the batteries get low.

The moral? Get yourself a Fluke. The amount of time spent on the go-back would have paid for the meter right there.
Dieseldan73
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Lol, it actually is a Fluke. A Fluke 337. All my meters are Fluke. Must have been a "fluke" that it was having issues.🤣😂
Birken Vogt
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A 337 is a very old meter. I had one and it was giving false readings too due to old age. I got rid of it quickly for the same reason. A lying meter is worse than none at all.

I suggest using a 115 or similar. An amp clamp is for measuring current and the voltmeter function is kind of an afterthought. You are a professional, you can afford to have more than 1 meter. I carry 3 on the truck most times, a 115, a 387 (I think) (big fancy amp clamp) and another odd one that does phase rotation. If any of them break, run out of battery, or give strange readings I can get a second opinion.
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