Generac Generator question...

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emahler

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Generac guys...we have a small problem...I hope...

we just hooked up a 15kw 1PH gen set (customer provided)

we installed a Generac ATS with an integrated panel (I don't have the model number off hand)

the service to the building is 3PH 208/120V.

we used a 2P 70A circuit breaker to feed from the utility, the Generator has a 65A CB in it.

When we hooked it up and started to run the procedures in the book, no problems.

did the manual startup...everything worked fine.

now, here is where the problem occurred....when we set the generator on Auto...

after about 10 seconds, it kicked the generator on, even though there was still utility power (we hadn't shut that down yet)

the generator ran for about 15 mins until we shut it down.

so the question is....was this supposed to happen? or could the fact that the utility provides 208V (instead of 240V) be an issue?

any thoughts?
 
emahler said:
now, here is where the problem occurred....when we set the generator on Auto...

after about 10 seconds, it kicked the generator on, even though there was still utility power (we hadn't shut that down yet)
Did you set exercise time?
 
My guess would be the ATS is detecting what it considers an under-voltage problem.... it's looking for 240 and sees 208.
 
480sparky said:
My guess would be the ATS is detecting what it considers an under-voltage problem.... it's looking for 240 and sees 208.

OK, if we have to be serious I agree, this sounds like a possibility. :grin:

I know with the ATS I am accustomed to this could be caused by any out of perimeter measurement, frequency, under over voltage etc. maybe even low oil pressure.
 
peter d said:
So I guess the next question is, can the setting be changed on the ATS without performing surgery?

The ones we would deal with it would be a simple in the field programing change.

With the Onans we use a lot the first thing to check is the setting to see what voltage system it is set for.
 
mdshunk said:
I sure hope that a genset wouldn't be designed to fire up if the oil was low.

I have had 8 cylinder Cats fire up with the alarm indicating no oil pressure.

It turned out the oil pressure sender was bad but I think it would fire up anyway and shut itself down shortly.

In my case the Cat gen Tech hit the stop button as soon as we noticed the low oil alarm.
 
480sparky said:
My guess would be the ATS is detecting what it considers an under-voltage problem.... it's looking for 240 and sees 208.

that was my thought, but there was nothing in the manual about it being a problem..
 
emahler said:
Generac guys...we have a small problem...I hope...

we just hooked up a 15kw 1PH gen set (customer provided)

we installed a Generac ATS with an integrated panel (I don't have the model number off hand)

the service to the building is 3PH 208/120V.

we used a 2P 70A circuit breaker to feed from the utility, the Generator has a 65A CB in it.

When we hooked it up and started to run the procedures in the book, no problems.

did the manual startup...everything worked fine.

now, here is where the problem occurred....when we set the generator on Auto...

after about 10 seconds, it kicked the generator on, even though there was still utility power (we hadn't shut that down yet)

the generator ran for about 15 mins until we shut it down.

so the question is....was this supposed to happen? or could the fact that the utility provides 208V (instead of 240V) be an issue?

any thoughts?

I had a factor fresh one with the same problem. It was a bad 16volt control transformer. Maybe yours has taps to bump it up.
 
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