Generator Problem

strauby21

Member
I have a car trailer (for racing) that is wired up with a 6 circuit panel. The panel is wired with a 10-4 SJ Cord and has a 30 amp plug to run off of a generator ( 240 v) . I am using a Yamaha EF6300 ISDE generator. When plugged into the 240v outlet. I have 250/125 volts at
the panel. With just the air compressor running the compressor barley turns over and will trip the generator. If I use the pigtail I have
and plug the trailer into the 110v outlet on the generator I can run everything in the trailer including , The air compressor a roof air
conditioner, 8' lights and 2 spot lights outside. any help on why I cant use the 220v on generator would be great. ( the generator is New)
 
I have a car trailer (for racing) that is wired up with a 6 circuit panel. The panel is wired with a 10-4 SJ Cord and has a 30 amp plug to run off of a generator ( 240 v) . I am using a Yamaha EF6300 ISDE generator. When plugged into the 240v outlet. I have 250/125 volts at
the panel. With just the air compressor running the compressor barley turns over and will trip the generator. If I use the pigtail I have
and plug the trailer into the 110v outlet on the generator I can run everything in the trailer including , The air compressor a roof air
conditioner, 8' lights and 2 spot lights outside. any help on why I cant use the 220v on generator would be great. ( the generator is New)
This is an inverter generator.

It sounds like all your loads are on one side of the 240 volt system. Your generator is good for over 45 amps at 120 volts, but a bit less than half that (22.9) at 240 volts. If the load was balanced, you may not have the problem. If you are trying to run 30 amps on one side of the 240 volt supply rated at 22.9 amps, you are overloading it.

It sounds like your trailer does not have a 120/240 volt system. It sounds like it only has 120 volts and the 240 volt connector is just for the convenience of being able to connect to a 240 volt source.

If you re-wire your panel to balance out the loads, remember that you will only be able to run half of the panel using a 120 volt plug.
 

templdl

Senior Member
Location
Wisconsin
Assure that your genset can handle the starting current of the compressor. Compressors sometimes are quite difficult to start and you're probably getting a voltage drop because the gen set is not capable of providing the starting current requirement.
 

hillbilly1

Senior Member
Location
Atlanta,Ga
Sounds like the generator does not have enough capacity for starting the compressor, especially with the compressor being 120 volt, if you change it to 240, you probably will not have a problem. You did not say what hp the compressor was?
 

hillbilly1

Senior Member
Location
Atlanta,Ga
Just re-read your post, I thought you were plugging into a regular utility receptacle not powered by the generator, but you are saying that it works on generator when using the duplex instead of the 4 wire 240?
 

mike_kilroy

Senior Member
Location
United States
if it is not that u have only 1/2 the generator amps avail on the 240v outlet as K8MHZ suggested, then it sounds like you have a loose wire on the 240v side. u did not say how old the trailer wiring is. things do come loose, especially things that bounce down the road....

harbor freight is ur friend. get a newspaper ad and go get one of their free (or $ 7) multimeters and measure the 240v voltage at your panel & compressor, especially when u turn on the compressor. with the meter's feedback I bet u can fix this yourself quickly!

AC8V
 
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if it is not that u have only 1/2 the generator amps avail on the 240v outlet as K8MHZ suggested, then it sounds like you have a loose wire on the 240v side. u did not say how old the trailer wiring is. things do come loose, especially things that bounce down the road....

harbor freight is ur friend. get a newspaper ad and go get one of their free (or $ 7) multimeters and measure the 240v voltage at your panel & compressor, especially when u turn on the compressor. with the meter's feedback I bet u can fix this yourself quickly!

AC8V
I think the compressor is 120 volts, so there would be no way to measure the 240v voltage at the compressor.

What looks to be an anomaly is the fact that all is well when fed with 120 volts, but a voltage drop and breaker trip is experienced when the exact same load is connected via the 240 volt feed from the genny.

The genny is only good for 22.8 amps at 240 volts. If the current exceeds that rating, on one leg or both, that would result in a voltage drop and a breaker trip. If that same load was connected to the 120 volt source, that is good for 45 amps and, thus, can handle twice the current at 120 volts as the 240 volt source can supply at 120 volts.

Let's say he's got a 40 amp draw on 120. That's fine. He is 5 amps under. Now let's say that same 40 is connected to the 240 volt supply, all on one leg. Well, you only get 22.8 amps. See the problem?

Now, if the load was split and balanced, say 20 on each leg, that same load would not be an overload to the 240 volt supply.

To verify:

Plug into the 240 volt receptacle and measure the current on all 4 conductors under full load. ANY measurement over 22.8 amps is an overload, while you get 45 amps out of the 120 volt receptacle.

Those are the specs from the nomenclature for the generator. Don't ask me how they get 45 amps to a single 120 volt outlet....they must use big wire!

That genny would be GREAT at field day!
 
Remember, this is not a regular generator.

This is a DC generator feeding an inverter to create AC. The engine only turns as fast as needed. No energy is wasted by having to keep an exact RPM regardless of load (or not).

It is the limitations of the inverter that affects the end user, not the limitations of the generator.
 
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