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Unbalanced load on generator supply

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BigN8

Electrical
Sep 29, 2006
1
I've got an application where I have shipping container that contains a piece of equipment(incinerator). This incinerator requires 120V/1PH/60HZ/30A service. The container also has another accessory circuit (lights, recept., and exhaust fan) @ 120V/1PH/60HZ/20A. These two circuits terminate at a 4-circuit loadcenter, with a 50A main. Under typical use, the equipment circuit will be using ~15A (running). The accessory circuit will be using just a fraction of that load (in the 2-3A neighborhood) I need to provide a generator to power this unit. I've got a 6kW generator at my disposal that is equipped with the following:

2 - 125V-20A duplex receptacle(s)(5-20R) - 2P3W
1 - 125/250V-30A socket (L14-30R) - 3P4W
1 - 250V-30A socket (L6-30R) - 2P3W

All the background aside, here is the question. I had originally planned on connecting the generator to the loadcenter via the 125/250V-30A connection, using the 2 hots (120V) to feed opposite sides of the bus in the loadcenter, with the ground and neutral shared with both circuits. My question is, in my application will the difference in actual current used by the two legs adversly effect the generator? I need to provide 30A to the equipment circuit, and I am somewhat stuck with the generator I've got. I have considered installing a 240/120 transformer between the generator and loadcenter which would essentially evely share the 240 among the two 120V loads. I am limited on space and cost and quite frankly a 10kVa Transformer takes up a substantial chunk of both. Can I safely run these two circuits off of the 125/250V-30A (3P4W) with out overloading the generator or damaging it?

Thanks for your input,

BigN8
 
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Yes.
There may be some voltage regulation issues, but they may either be resolved or possibly ignored.
I would first try the 125/250 V, 30 amp output and check the voltages on both lines to neutral.
The voltages will probably be acceptable. A voltage range from 110 volts to 125 volts is good. 105 volts to 130 volts is probably acceptable.

If the voltages are too far off, try putting the heaviest load on one leg of the 125/250 V, 30 amp outlet and measuring the voltages at the 125 v, 20 amp outlets. If you find a voltage that you can use, connect the smaller load to that output.
15 Amps + 3 Amps 18 amps. 18 amps x 125 volts = 2250 Watts.
Even if you end up with the total load on one side of the line, this should be safe for a 6KW generator.
There should be no issues with the generator, but, as I have mentioned there may be voltage balance issues. If your load can accept the voltages resulting from unbalanced loading, then you are OK.
I am optomistic of your chances of success.
respectfully
 
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