Can I test/measure the load at my generator?

[ljjhouser]

a clamp on meter would be great but it wont work on the 50 amp cable plugged into the generator. My generator is 25 feet from the 50 amp outlet coming from the panel. It would be interesting somehow to have a readout mounted to the generator showing live output load.

I think clamp on only works on one wire. The hot wire. If so, might build a 2' adaptor cable female end-2' cable with SEPARATE wires - male end. Temp to measure current draw. Then you can run it and have the neutral, ground and power separate.

 

[ljjhouser]

How do you get it to read 220V? run the 2 legs through the clamp together?

Measure each leg of the 220 separate. Add them up. For example. A home central air may run off a 30-amp 220 breaker. The breaker has two 120 feeds. Each feed (connection to the breaker) may measure up to 30 amps, meaning the total current maybe 60 amps. Since the compressor requires 220 volts, most 220 breakers are fused together so that you cannot turn on only one. Hope this helps a little. I must mention, exercise caution to be safe. DO not do much of this unless you really understand what you are doing. And don't do it standing on concrete. Just be careful.

 

[JCoastie]

I also like fluke. Just didn't want the OP to think that was the only way to go when he saw the prices. When taken care of, Fluke seems to last forever.

Display on my Fluke 87 is crapping out. I read somewhere that they are warrantied forever, so I called fluke about 2 months ago. Nope, out of warranty, they wanted ~$350 for a new one. It's not like most homeowners (like I am now) are calibrating their meters every year (or at all) so no need for a Fluke, and the inexpensive (inexpensive not cheap!) ones these days are pretty great.

 

[ljjhouser]

Display on my Fluke 87 is crapping out. I read somewhere that they are warrantied forever, so I called fluke about 2 months ago. Nope, out of warranty, they wanted ~$350 for a new one. It's not like most homeowners (like I am now) are calibrating their meters every year (or at all) so no need for a Fluke, and the inexpensive (inexpensive not cheap!) ones these days are pretty great.

I think all my Fluke meters are more than 20 years old. If I had to replace them, I would not pay want they want for them today.

 

[grsthegreat]

it doesnt need to be fluke, but it HAS to be rated TRUE RMS to measure generator voltage correctly. generators only have 2 or 4 poles so create a dirty sine wave compared to utility that can have 72 poles on a hydroelectric generator rotor.
i cant count the number of service calls ive done because someone says their generator isnt operating correctly. . .only to find out their meter isnt reading correctly.

 

[WranglerX]

find something like this to plug into the genny outlet if it is a plug in genny.

https://www.amazon.com/Digital-Wattmeter-Consumption-Frequency-Electricity/dp/B0828QWQZP/ref=sr_1_5?keywords=killawatt+220v&qid=1659466874&sr=8-5

How do I plug in my NEMA 14-30P into it....

 

[workinonit]

it doesnt need to be fluke, but it HAS to be rated TRUE RMS to measure generator voltage correctly. generators only have 2 or 4 poles so create a dirty sine wave compared to utility that can have 72 poles on a hydroelectric generator rotor.
i cant count the number of service calls ive done because someone says their generator isnt operating correctly. . .only to find out their meter isnt reading correctly.

I know you work with small generators but dirty power has nothing to do with the number of poles a generator has. Almost all commercial generators are either 2 or 4 pole. Hydros and wind turbines are the exception but those have nothing to do with the quality of the power but instead the ability of the driver to make required speed(RPM).

Almost any pabnel or hand held meter these days will read RMS. Peak-peak voltage would mean nothing to the average person.

In my opuinion, the most important measurement on small generators gets overlooked. My monitored reading when I start up my PTO driven gen is frequency. Obviously freq and voltage are directly proportional but the voltage ban on most equipment is very broad compared to the frequency tolerance.

 

[grsthegreat]

I know you work with small generators but dirty power has nothing to do with the number of poles a generator has. Almost all commercial generators are either 2 or 4 pole. Hydros and wind turbines are the exception but those have nothing to do with the quality of the power but instead the ability of the driver to make required speed(RPM).

Almost any pabnel or hand held meter these days will read RMS. Peak-peak voltage would mean nothing to the average person.

In my opuinion, the most important measurement on small generators gets overlooked. My monitored reading when I start up my PTO driven gen is frequency. Obviously freq and voltage are directly proportional but the voltage ban on most equipment is very broad compared to the frequency tolerance.

I dont agree. Simple test is to put oscilloscope on a 2 pole, then a 4 pole Generator. Major difference.

also, heres a great discription i found awhile ago

An average-responding meter uses averaging mathematical formulas to accurately measure pure sinusoidal waves. It can measure non-sinusoidal waves, but with uncertain accuracy. A more sophisticated true-RMS meter can accurately measure both pure waves and the more complex non-sinusoidal waves.

generators do not put out true waves. And number of poles on a generator greatly affect quality of power. An oscilloscope on utility power shows a very clean sine wave, especially compaired to a generator.


and all meters do not work great on smaller generators. I have in field, actual knowledge of this fact.

 

[bitseeker]

Is there a way when the generator is running with a load to measure the load ? at the generator itself?

Yes there is. I just bought an energy monitor from Emporia: Smarter Home Energy Management .
The basic $85 kit will do what you want.
It will do LOTs more than what you want.
The equipment is top-quality.
The company is in Colorado.
The service and support are the best I have experienced.
Humans with expert knowledge promptly answer the phone and emails.

Except as a satisfied customer, I have no association with the company.

 

[npalen]

Measure each leg of the 220 separate. Add them up. For example. A home central air may run off a 30-amp 220 breaker. The breaker has two 120 feeds. Each feed (connection to the breaker) may measure up to 30 amps, meaning the total current maybe 60 amps. Since the compressor requires 220 volts, most 220 breakers are fused together so that you cannot turn on only one. Hope this helps a little. I must mention, exercise caution to be safe. DO not do much of this unless you really understand what you are doing. And don't do it standing on concrete. Just be careful.

I don't think you "add them up". The total amperage draw is shown when measuring either of the two legs.
Also, why would concrete be any worse than standing on turf, for example?