GFCI Tripping on Inrush

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wptski said:
If there's no such thing as "nuisance tripping" there sure is lots on the net covering the subject! Mostly refering to the cause being harmonics.
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I think blaming 'harmonics' is absolutely with out merit.

How much 'harmonics' can be expected in home electrical system.
 
iwire said:
I think blaming 'harmonics' is absolutely with out merit.

How much 'harmonics' can be expected in home electrical system.
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I've read >3% THD in voltage can be a problem but also >5% too!

In my home, most often on days where the temperature is going to be in the eighties, my normal of around 2% THD will spike at between 6:15am-6:32am. This morning at 6:17am it was 14.8%. POCO is doing something at that time.

I've seen 34.9% THD during a good thunderstorm. One day it stayed just above 3% for three or four hours.
 
wptski said:
I've read >3% THD in voltage can be a problem but also >5% too!

In my home, most often on days where the temperature is going to be in the eighties, my normal of around 2% THD will spike at between 6:15am-6:32am. This morning at 6:17am it was 14.8%. POCO is doing something at that time.

I've seen 34.9% THD during a good thunderstorm. One day it stayed just above 3% for three or four hours.
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And during these times, how many GFCI devices tripped for no apparent reason. For that matter what effect, affect or damage have you noticed?
 
wptski said:
I've read >3% THD in voltage can be a problem but also >5% too!

In my home, most often on days where the temperature is going to be in the eighties, my normal of around 2% THD will spike at between 6:15am-6:32am. This morning at 6:17am it was 14.8%. POCO is doing something at that time.

I've seen 34.9% THD during a good thunderstorm. One day it stayed just above 3% for three or four hours.
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I won't ask why your monitoring THD at your home....

However I will ask you how you believe harmonics will trip a GFCI device.

I went searching last week when this came up and the most credible thing I found was an old IAEI article that mentioned that UL has not investigated how harmonics effect a GFCI.

No mention of there being a problem only that they have not specifically looked for one.
 
iwire said:
I won't ask why your monitoring THD at your home....

However I will ask you how you believe harmonics will trip a GFCI device.

I went searching last week when this came up and the most credible thing I found was an old IAEI article that mentioned that UL has not investigated how harmonics effect a GFCI.

No mention of there being a problem only that they have not specifically looked for one.
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I'll answer that anyway. I used a Ideal 61-830 VPM.

I replied to a post mentioning that there is no such thing as "nuisance tripping" of GFCI or just breakers of any kind! I didn't say that THD would trip a GFCI either.

Not one GFCI in my home.
 
jim dungar said:
And during these times, how many GFCI devices tripped for no apparent reason. For that matter what effect, affect or damage have you noticed?
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No GFCI's tripped becasue I have none. You guys are misreadings my post. I replied to a post saying that there is no such thing as "nuisance tripping" of anything! High THD is at times blamed for "nuisance tripping" of breakers on circuits for VSDs mostly used in industry although they are starting to use them in air handlers in HVAC applications.
 
Repeating My Earlier Post

Repeating My Earlier Post

wptski said:
No GFCI's tripped becasue I have none. You guys are misreadings my post. I replied to a post saying that there is no such thing as "nuisance tripping" of anything! High THD is at times blamed for "nuisance tripping" of breakers on circuits for VSDs mostly used in industry although they are starting to use them in air handlers in HVAC applications.
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If there is nuisance tripping, explain what the nuisance is. Is it having to reset a breaker that has tripped or is it having to explain to the customer why you or someone else has to keep making return trips to reset a breaker that keeps tripping out and you cannot explain why.

Any overload or overcurrent device trips for a reason- please explain to me why it does not.I'm open for suggestions.

This is not meant to be a p--sing contest, just a search for knowledge.:confused:
 
masterelect1 said:
If there is nuisance tripping, explain what the nuisance is. Is it having to reset a breaker that has tripped or is it having to explain to the customer why you or someone else has to keep making return trips to reset a breaker that keeps tripping out and you cannot explain why.

Any overload or overcurrent device trips for a reason- please explain to me why it does not.I'm open for suggestions.

This is not meant to be a p--sing contest, just a search for knowledge.:confused:
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How's this?

Nuisance trips are clearly defined as unwarranted circuit breaker trips with either no electrically based reason for the trips, or, the breaker deems there to be a fault when one does not exist.
 
Pierre C Belarge said:
If the appliance trips the GFCI protection (and not the standard breaker), would it not make sense that possibly there is some kind of ground fault within the appliance????
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It does indeed! That a standard breaker would not trip is why they call it a nuisance.

Either way, it's still the fault (pardon the pun) of the appliance.
 
A GFCI Breaker will trip for four reasons and four reasons only:
1. There is a ground fault exceeding the trip point of the breaker.
2. The circuit is overloaded beyond the capacity of the breaker.
3. There is a fault to ground or short circuit which creates an amp draw in excess of the capacity of the breaker causing it to trip.
4. The breaker is defective.
Which of these is "nuisance tripping"?
All of these conditions indicate a problem and that remedial action is required. There is no such thing as nuisance tripping. Any time a circuit breaker trips, or a GFCI device opens, it is an indication of a problem, which is why the device was installed!
 
haskindm said:
There is no such thing as nuisance tripping. Any time a circuit breaker trips, or a GFCI device opens, it is an indication of a problem, which is why the device was installed!
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I agree.

Very few electricians I know would rip out a standard breaker and replace it with a larger one 'because it's tripping'. They would investigate the cause and fix it.

On the other hand the first reaction many seem to have if a GFCI trips is to simply remove the GFCI 'because it's bad' and replace it with a non GFCI breaker. To me this makes no sense.

The GFCI in not likely tripping becuase it's bad, it's tripping because there is something it is protecting personal from.
 
haskindm said:
A GFCI Breaker will trip for four reasons and four reasons only:
1. There is a ground fault exceeding the trip point of the breaker.
2. The circuit is overloaded beyond the capacity of the breaker.
3. There is a fault to ground or short circuit which creates an amp draw in excess of the capacity of the breaker causing it to trip.
4. The breaker is defective.
Which of these is "nuisance tripping"?
All of these conditions indicate a problem and that remedial action is required. There is no such thing as nuisance tripping. Any time a circuit breaker trips, or a GFCI device opens, it is an indication of a problem, which is why the device was installed!
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You may think that there is no such thing as nuisance tripping because your field is too limited or your not opened minded enough.
 
Bill,
We are all here to learn and help the trade. If there is another situation that will cause a breaker to trip other than the ones that I listed, I would be interested in knowing what it is. I did not say that it was not a NUISANCE when a breaker trips, but the term nuisance tripping indicates that a breaker is tripping for no good reason. I maintain that such a situation does not exist. If breaker trips, there is a reason and remedial action should be taken. It could be that the breaker is defective, but that is still not nuisance tripping; it is a defective part. It is no more nuisance tripping than a breaker that trips because a conductor is defective and shorting to the metal conduit.
 
iwire said:
Very few electricians I know would rip out a standard breaker and replace it with a larger one 'because it's tripping'. They would investigate the cause and fix it.
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We tried. A repeat customer of ours had a breaker that kept tripping and taking out her garden fountain. It wasn't a GFCI breaker; that was in the receptacle in the back yard. :-?

It turned out that someone had run the yard receptacle from the garage receptacle circuit. A quick clamp-on test confirmed that the 15a breaker was doing its job at 18 to 19a. :cool:

We recommended running the yard receptacle directly to the panel on its own breaker. She countered that she heard replcing the 15a breaker with a 20a would stopp the tripping. :mad:

We explained about the danger and illegality of doing so, and that we cannot do as she asked. She said she'd find someone who would. Next time we saw her, we asked about it. :confused:

She proudly said that she found a guy who was happy to. We reiterated why we couldn't have, why the other guy shouldn't have, and that we couldn't do any more work for her. :mad:

Oh, well. :roll:
 
wptski said:
You may think that there is no such thing as nuisance tripping because your field is too limited or your not opened minded enough.
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Bill, what condition would you consider legitimate nuisance tripping, i.e., tripping of a GFCI device (or any other, if you like) that is not indicative of a genuine electrical concern?
 
From Delmar's Standard Textbook of Electricity, Third Edition, pages 21 &22. "Another advantage (GFCI recps over GFCI breakers) is that, since they are located at the point of attachment for the device, there is no stray capacitance loss between the panel box and the equipment being protected. Long wire runs often cause nuisance tripping of GFCI circuit breakers"


I start school in a week, wish me luck!!!:grin: :D
 
andinator said:
From Delmar's Standard Textbook of Electricity, Third Edition, pages 21 &22. "Another advantage (GFCI recps over GFCI breakers) is that, since they are located at the point of attachment for the device, there is no stray capacitance loss between the panel box and the equipment being protected. Long wire runs often cause nuisance tripping of GFCI circuit breakers"


I start school in a week, wish me luck!!!:grin: :D
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What a way to start! Rocking the boat.:grin:
 
A construction electrician which is mostly if not all thats here won't see the problems a industrial electrician who are becoming more electronics technicians will see like nuisance tripping.

All you have to do is Google "nuisance tripping" and read up.
 
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