125.1v off my generator?

[Wade Lippman]

I just bought a Champion 2000w inverter generator. Starts easily and runs a 1750w load just fine. It is surely not as quiet as a Honda, but they are more than twice the price.

BUT, it puts out 125.1v at no load; dropping to 121.5v at 1750w load. The 125.1v is somewhat more than the 4% allowed utilities. Should I care?

Returning it locally will not be a problem, if it comes to that.

[Lee Schierer]

I routinely have 123 volts in my house with no load. The other factor is how well calibrated is the meter you are measuring the voltage with.

[Ken Fitzgerald]

It sounds like a normal condition for a "no load" situation.

Does the manual specify what the no load voltage should be?

[Marty Gulseth]

Hi Wade,

As respectfully as possible - I suggest that you double-check your permissible variation for the local utility. In WA state, the maximum permissible voltage variation from nominal is plus or minus 5%, the maximum permissible change (minimum to maximum voltage) is 8%. (WAC 480-100-373) I'm pretty sure most state or local codes reference the NEC or NESC (I think NEC is applicable in this case) so I suspect yours is the same.

As a practical consideration, although I'm no expert on portable generators, I would not offhand find the behavior you describe unreasonable.

Regards,

Marty

[Wayne Lovell]

I worked for Houston lighting & Power for 27 years, in Texas the allowable variation is + or - 5%. Electrical equipment is designed to operate at + or - 10% without damage. It is better to be on the high side than the low side, we always tried to be on the high side(most customers had about 124V at the meter) this helped to allow for voltage drop because of distance or maxing out on the customers wiring.

[Wade Lippman]

I thought it was 4%.
Champion says they set it for 125v so it is still above 120v when loaded. Whatever...
But I guess it is okay, and possibly proper. Thanks.

My home voltage at the panel is 123v in the winter and 117v in the summer. Apparently the utility lines weren't sized for airconditioning.

[Art Mann]

Standards are not the same nationwide. I had problems with low voltage in our neighborhood during the drought last summer. My shop voltage was 109 VAC. The utility guy came out to check it. He acknowledged a problem but said their specification is +/- 10% of 120 VAC. My problem turned out to be a squirrel who gnawed the uninsulated aluminum neutral wire almost in two.

[Steve Peterson]

I usually measured between 126V and 127V on the wall outlets at my old house. We never had any problems with electronics burning up or light bulbs burning out too quickly. It should be fine.

Steve

[Bill Graham]

I just bought a Champion 2000w inverter generator. Starts easily and runs a 1750w load just fine. It is surely not as quiet as a Honda, but they are more than twice the price.

BUT, it puts out 125.1v at no load; dropping to 121.5v at 1750w load. The 125.1v is somewhat more than the 4% allowed utilities. Should I care?

Returning it locally will not be a problem, if it comes to that.

No, not at all. Nominal US single phase voltage has been considered anywhere between 110-130 with 120 considered a happy medium. I don't know where your 4% deviation comes from but when I worked for the power company it was 110-130.

Best,
Bill

[Brian Elfert]

Generators generally don't regulate voltage as well as the grid. My expensive 8KW diesel generator will do around 127 volts at no load, but I have seen close to 110 volts with a really heavy load. I had to replace the voltage regulator once already as voltage was dropping to well under 100 volts at times. I still have a problem where sometimes the voltage drops way down with all three A/C units running and tech support says to replace the regulator again.

[Mike Cutler]

Wade

What are you running with the generator?
Your voltage is fine. I'd be more concerned with the output frequency and wave signature. Which may account in part for why the Honda cost so much more. Honda has some nice inverter technology in their larger home generators. Not sure about the smaller models.

[Wade Lippman]

It holds 60hz regardless of load.
It claims to be within 3% of a perfect sinewave; no way to test it though.

Actually it holds voltage better than the utility. At no load the generator is 125v and the outlet in my garage is 123v. With a 1800w heat gun the generator is 121v and the outlet is 118v. Of course the outlet is at the end of maybe 80' of cable.

I just want to be able to run the furnace, refrigerator and internet is worst comes to worst.

[Mike Cutler]

It holds 60hz regardless of load.
It claims to be within 3% of a perfect sinewave; no way to test it though.

Actually it holds voltage better than the utility. At no load the generator is 125v and the outlet in my garage is 123v. With a 1800w heat gun the generator is 121v and the outlet is 118v. Of course the outlet is at the end of maybe 80' of cable.

I just want to be able to run the furnace, refrigerator and internet is worst comes to worst.

Wade

I think you're fine.

[John K Jordan]

It holds 60hz regardless of load.
It claims to be within 3% of a perfect sinewave; no way to test it though.
...
I just want to be able to run the furnace, refrigerator and internet is worst comes to worst.

I have an older Honda generator that claimed a good sine wave. In practice, there was a lot of noise on the signal - any variation in the sine wave can generate high frequencies which should work fine with a fridge but not with some electronic devices. I hoped to use mine with my computer workstations but it tripped a good UPS repeatedly so I gave up. Perhaps new generators are much better and yours is cleaner.

There is a way to test the output waveform: look at the signal with an oscilloscope. Best to test it under load. I realize not everyone keeps an oscilloscope (I'd hate to be without mine) but a local electronics geek, shop, or makers club could do it. Or one with no display that connects to a computer is cheap.

JKJ

[Art Mann]

John, the generator you are using is probably not an inverter style generator like the one the OP owns. Synchronous generators develop more harmonic distortion the heavier they are loaded but the inverter generators don't do that (much). I am one of those people who owns a digital storage oscilloscope and I use both types of generators. My synchronous generator output gets really ugly at full load. I used it that way when a tornado came through our community and disabled power for 5 days. I tried to run a single eye on the electric stove, which it should have been able to do, and the output was so bad that the digital control panel on the stove quit working.