Can I test/measure the load at my generator?

   / Can I test/measure the load at my generator? #13  

5030

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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.
Not something I've ever required. My standby is a diesel powered (John Deere) Generac 4 pole skewed wound head turning at 1800 governed rpm. It's rated at 34KW continuous and for my purposes, it's fine the way it is. Never loaded it to maximum rated output.
 
   / Can I test/measure the load at my generator? #14  

ptsg

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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 mounted three of these (one per phase) on the control box of my 10kw generator when I restored it. About $4 each. There are fancier ones available. It's always there, I can always get a reading on it and basic math will give me the Watts if I really need.

Here I was charging my 70's electric forklift just to load the generator a little bit. 236V * 21.8A = 5144 W

IMG_20211201_164158.jpg
 
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   / Can I test/measure the load at my generator? #15  

JCoastie

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on mine, all the cables run inside a rubber sheath from the generator (round bottom portion) to the front panel. I'm still deciding if I want to open that sheath so I can access the individual wires with a clamo on meter, or just install a power display, something 'like" this, https://www.amazon.com/CrocSee-CRS-022B-Frequency-Multimeter-Transformer/dp/B07K3S4K9L

If you remove the 2 bolts from the end of the round generator, and pull the round cover off, all the wires are accessible to hook it up.
 
   / Can I test/measure the load at my generator? #16  

npalen

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   / Can I test/measure the load at my generator?
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Rebeldad1

Rebeldad1

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on mine, all the cables run inside a rubber sheath from the generator (round bottom portion) to the front panel. I'm still deciding if I want to open that sheath so I can access the individual wires with a clamo on meter, or just install a power display, something 'like" this, https://www.amazon.com/CrocSee-CRS-022B-Frequency-Multimeter-Transformer/dp/B07K3S4K9L

If you remove the 2 bolts from the end of the round generator, and pull the round cover off, all the wires are accessible to hook it up.
How do you get it to read 220V? run the 2 legs through the clamp together?
 
   / Can I test/measure the load at my generator? #18  

grsthegreat

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i agree with alot of the above, but for a dirty generator power you need a true rms style meter.

im not sure if those cheap add on meters are giving a true rms reading. never really looked into it.

they do look pretty though.


on my own generator i use the Genmon system. its hooked into my wifi. i can see real time readings on it. also alerts me to power outages, errors, etc.

(heres a quick screen grab)

Untitled.jpg
 
   / Can I test/measure the load at my generator? #19  

ljjhouser

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I concur but I buy quality stuff and Fluke is quality plus if it read a certain amperage or voltage you can take that to the bank as correct.
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.
 
   / Can I test/measure the load at my generator? #20  

JCoastie

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How do you get it to read 220V? run the 2 legs through the clamp together?
the clamp (current transformer) measures current/amps, not voltage.
2 additional wires on the meter connect to both hot wires to get the voltage 240v reading. (or 1 hot and a neutral to read 120v)

Since things on the circuit can use 120v loads, (microwave, TV, fans etc) the best option is to run 2 of those current sensing meters, one on each leg, and the higher reading of the 2 legs is your total current draw.
(120v loads depending on which side of the breaker panel they are installed on) will use one hot leg and the neutral, this is why you want to monitor both hot legs, and use the higher of the 2 current values. Don't add them together, just read the higher value.

Another example, your cloths dryer is probably 240v, the heating element will use 240v (both hots) but the motor that spins the drum and the electronic touch panel will use 120v (1 hot and the neutral) so one of the hot lines will show a higher current draw than the other. This along with which sides of the power panel your loads are on, is why you want to monitor the current of both hot legs and read the higher of the 2. (the difference of the 2 is carried by the neutral)
 
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