afci on portable generator

[ceb]

I am completing a home remodel after a fire today I hooked my portable gen. to the panel to check out the system. (meter had been pulled due to fire) every thing was ok until I turned on the afci breaker for the bedrooms it would instantly trip. I checked and turned off all lights on the circuit and it still would trip. The only thing that would be on are the smoke detectors. My thought is my gen. puts out around 130v per leg and that voltage fluctuates I am thinking its that fluctuation that would cause the afci to trip. I had powered this panel before with reg. breakers and found no problem. Does any one have any thoughts on this problem?

 

[pierre]

Re: afci on portable generator

Ceb
You need to be realistic about the possible fire damage to the wiring in the areas that are controlled by the AFCI. If there is a chance that damage occurred to the wiring, maybe you should think about meggering the circuits that may have been damaged. I would be very leary if a regular breaker holds, and a AFCI trips.

Pierre

 

[tonyi]

Re: afci on portable generator

Originally posted by ceb:
I had powered this panel before with reg. breakers and found no problem. Does any one have any thoughts on this problem?

A bootleg ground is usually a guaranteed trip an AFCI.

If older light fixtures were salvaged and reused check'em out. Some don't have a proper gnd wire, just a bond strap from the neutral to the fixture's housing. In a plastic box, this wouldn't cause a problem, but in a properly grounded metal box, the fixture mount screws will essentially create a hard wired bootleg between the box gnd and neutral and divert enough neutral current down the gnd to cause the AFCI's 50ma GFCI aspect to trip.

 

[ceb]

Re: afci on portable generator

I reused NO fixtures. All recpt. were replace. All new wiring to smoke dect. ( had to bring into code all bedrooms and hall) Their was no fire damage in that part of home just smoke.

 

[tonyi]

Re: afci on portable generator

Originally posted by ceb:
I reused NO fixtures. All recpt. were replace. All new wiring to smoke dect.

I'd put the regular breaker back in temporarily, then check the branchs gnd wire with a probe that will go down to the milliamp level. If there's any measurable current on the gnd wire, then there's probably a bootleg somewhere. Doesn't take much to trip an AFCI - most trip in the 50ma+/- range.

There may also be a genuine arc happening somewhere too. Was this a metal or plastic boxes job?

Basically start following the diagnostic procedure on the papers that come with the AFCI. Start isolating parts of the branch until you locate the section causing the problem. This can be a PITA

 

[ceb]

Re: afci on portable generator

all plastic. I started the process of checking the circuit their are three light fixtures, six recpt. and the smokes all new. no lights were turned on nothing plugged in the only thing that could come to life are the smokes. That is why I am wondering about the gen. that was powering the system at the time.

 

[tonyi]

Re: afci on portable generator

To quickie check the generator theory you could disconnect the offending branch completely and hang just a keyless lampholder and a bulb off the AFCI.

 

[hurk27]

Re: afci on portable generator

Ceb:
You mention the generator was giving you 130 volts.
This is a good sign that the generator is over speed. this will cause the frequency output of the generator to be high. A AFCI has components in it to monitor line frequency to detect a arcing signal and this is what is probably causing your tripping. If you have a digital meter that will read frequency use it to set the generator's RPM's to the correct speed.

 

[hbiss]

Re: afci on portable generator

I'm willing to bet that the generator power is noisy and is causing those AFCI's to trip. Wait until the service is restored before pulling your hair out.

 

[Guest]

Re: afci on portable generator

Can you run a widowmaker cord from a neighboring house to test the AFCI breaker? Or, can you take it to another house with known good working AFCI circuits?

[Edit add: Don't really use a widowmaker!].

[ November 03, 2003, 05:14 PM: Message edited by: awwt ]

 

[ceb]

Re: afci on portable generator

Sorry,AWWT I don't carry 1 1?/2 miles of drop cord I am having final insp. today if every thing goes ok I hope to have normal power on to the house by Wed. I am hoping the gen. is the problem if not o'well here we go

 

[don_resqcapt19]

Re: afci on portable generator

Wayne,

Can you run a widowmaker cord from a neighboring house to test the AFCI breaker?

I assume that you are suggesting the use of a double male cord. Violations of safety rules should never be suggested on this forum.
Don

 

[bill addiss]

Re: afci on portable generator

ceb,

Did you check for a Neutral to Ground connection somewhere in the circuit? The AFCI has a GFCI component that will cause a trip if say a bare ground was touching a neutral screw on a device. Any nicked wires? A nicked neutral can contact a Bare ground when wires are folded back in the box sometimes.

Bill

 

[Guest]

Re: afci on portable generator

Don,
I was trying to make my posting sound sexier. It was pretty dry without the word widowmaker. Sorry to walk on the rules. I don't expect anybody to do anything unsafe

 

[iwire]

Re: afci on portable generator

Originally posted by don_resqcapt19:
I assume that you are suggesting the use of a double male cord. Violations of safety rules should never be suggested on this forum.
Don

Don I agree that this is a dangerous practice and should not be encouraged.

But have you seen the threads which point out this is exactly how people in some areas get their final inspection.

They back feed the dryer outlet from the temp service.

I find this very odd and disturbing.

 

[tom baker]

Re: afci on portable generator

A AFCI has a built in GFCI circuit, usually trips at 30 mA. 95% of all afci trips are from inadvertant neutral to ground connections.

 

[csw]

Re: afci on portable generator

I deal with womack electric , and , they told me that the first afci breakers ( the short ones ) had problems tripping . ( cutler hammer )

 

[jimwalker]

Re: afci on portable generator

I was gonna suggest bypasing meter with jumpers
but i won't
Our local poco don't get too upset over this as long as sparky is on the job and it's only for a hot check. Resail when finished.

 

[jimwalker]

Re: afci on portable generator

Why wasn't there a T pole
Ive done lot's of fire jobs here. Often the place is still smoking and we are seting T so they can use fans to dry the water up.Did all the subs use gen. to do remodel ? OUCH