Why do these GFCI receptacles trip?

Age and cheap brand.

KenW

Reply to
KenW
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In my 10 year old home I am having trouble with a couple GFCI receptacles. But I think the problem is probably with every one in the house, as they are all the same age and brand. In the bathroom when I turn off the hair clippers I use for beard trimming the GFCI almost always trips. But only when the clippers are being turned off. In the basement we have an twenty year old washing machine that we kept to use in case the upstairs new washer needed repair, which has ben more than once. When the washer changes cycles it will randomely trip the GFCI. Like the upstairs GFCI it only happens when the load is removed from the GFCI. For example, the water valve solenoids, when switched off by the washer, will cause the GFCI to trip. Or when the washer motor is turned off when it changes speed. Do I need to buy better GFCI receptacles? Or is this just because the things are generally so sensitive to arcing when a contact opens that any brand will show the same behavior/ Thanks, Eric

Reply to
etpm

GFCI devices have a service life of about ten (10) years in a dry location, and anywhere from 2-5 years in a damp location. In many cases, their effec tiveness as a ground-fault devices is long-gone, whereas they will still fu nction (somewhat) as a normal breaker. There are exceptions - see monthly t est below.

Yes, DO test them every month as suggested. YES, DO replace them IMMEDIATELY the moment they display any sort of wonkin ess.

FULL STOP.

Peter Wieck Melrose Park, PA

Reply to
peterwieck33

Thanks Peter, I do test most of the GFCI receptacles monthly. They always pass. So I'll replace the two and see what happens. Eric

Reply to
etpm

This explains what might be happening and how to troubleshoot it:

Duz the house have aluminum wiring? I've seen similar problems caused by aluminum wiring at a friends house: We traced the problem down to loose screws on the wall outlets and GFI receptacles. Tightening everything down make the false trips disappear for about 6 months, when they came back from the dead initially on anything that drew high current. The owner then tightened down the screws again, which again fixed the problem for a few months. I think you can see where this is going. The aluminum wires were being squashed by the brass screw and cold flowing until flat with the added bonus of some galvanic corrosion in the bath and laundry rooms. In the end, he installed copper wire pigtails and anti-oxidation goop on all the outlets, which I think finally solved the problem:

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Reply to
Jeff Liebermann

Don't use them on washing machines, dryers or refrigerators.

Whatever the code says, if your house was built 10 years ago then whatever the code said then goes, or at least you can make go.

If it has a 3 prong plug and you have a properly grounded outlet you don't need it. You are not required to update except in certain cases. Just make sure the ground connections are tight.

May not quite be code but it solves the problem once and for all, and as lo ng as those grounds are good, you will not die. Make SURE.

I read a bit and it does appear there is a little wiggle room on it, and th en they say a whole 60 people died from electrical shocks last year. And th en so many by fires, many more in fact. A GFCI does not protect against fi res, only ground faults.

After you put regular outlets in for your 3 prong grounded appliances that have motors, do nothing. However I am not so sure about if you use those cl ippers in front of a sink. Too many other things can be plugged in there an d the clippers are not usually 3 prong grounded, that one might have to say and either put up with it or try a newer GFCI. In that case I DO NOT recom mend offing the GFCI. In fact not at all, it will solve the problem though.

Reply to
jurb6006

"Does Your Washing Machine Require GFCI Protection" The washing machine outlet itself does not require a GFCI outlet, however any outlet within 6 feet of the outside edge of the sink in laundry rooms require that it be GFCI protected.

More detail: "Do washing machines require GFCI protection?"

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Reply to
Jeff Liebermann

Ground faults are not used on things that must run such as refrigerators and freezers. If they trip for some reason you can loose all your stored food. I think there is a code that covers that.

Reply to
Ralph Mowery

We had a thread on this very recently in sed. GFCIs are unbalanced at relat ively high frequencies, the result being they tend to trip on arcing. Of co urse that doesn't rule out your GFCIs being faulty or substandard, or your washing machine having N-E leakage.

NT

Reply to
tabbypurr

n, and anywhere from 2-5 years in a damp location. In many cases, their eff ectiveness as a ground-fault devices is long-gone, whereas they will still function (somewhat) as a normal breaker. There are exceptions - see monthly test below.

iness.

Ha ha, 'wonkiness'.

Reply to
bruce2bowser

Thanks for the links Jeff. The house is only about ten years old and was built for us and we are the only people who have ever lived in the house. So I know the history of the house which helps. I'll check out those links today. Eric

Reply to
etpm

The clippers are used in the bathroom so I will need to get that GFCI sorted out. Even if it means buying rechargeable clippers. The basement GFCI is also near a sink. But even if I put in another non GFCI receptacle away from the sink it will need to be connected to the same wires that feed the GFCI. I wonder if the wiring in the new receptacle before the GFCI will prevent tripping? In any case I am going to change out my old GFCIs in at least two places. Eric

Reply to
etpm

Between the washer hoses and cord you might be able get 6 feet away. Not so sure that would satisfy code because there is still water in the washer. H owever, do you need a GFCI where there might be a bucket of water ? What ab out if your garden hose is long enough and you decide to use it to wash the basement floor ?

At least that is some kind of rationale, if you do that make SURE that grou nd wire is tight.

Not so in the bathroom. Perhaps one of those strips audiophiles use to keep RF out of their stereos. The filtering should work both ways. If a new GFC I there doesn't help that may be your only solution.

You said you kept an old washing machine around for when the new one breaks ? I suggest you never get rid of it. In this area water is pretty cheap an d I have no use for a washing machine with a microprocessor and inferior re lays and valves, and probably plastic parts that should not be plastic. In other areas water is much more expensive and it may be worth it for them.

One thing about older dryers - on ours the door is pretty stout and opens d own. That means you can just throw the clothes over, walk over and scoop th em in a couple of times. If it opens to the side you have to get a basket, probably the same one your dirty clothes came in, put the WET clothes in th ere which is when they'll pick up the maximum dirt, carry the basket, possi bly around the door if it opens the wrong way for the layout of your baseme nt, and then put in only how much fits in your hand scoop by scoop.

Reply to
jurb6006

OK - let's cut to the chase:

GFCI devices are designed to save lives under specific conditions. Under th ose same conditions, they can be inconvenient. That is a given.

What they do: They detect current flowing from the hot line, and not retur ning via the neutral line. If they detect this condition of more than a ver y, very few MA, they trip. Meaning that they WILL NOT protect anyone delibe rately inserting themselves into a circuit. This despite sincere and touchi ng wishes otherwise.

Some devices will trip a GFCI pretty much most of the time. However, that t his happens DOES NOT make the GFCI device faulty. It makes the device fault y. What the device is doing is getting current from the hot side and sendin g it somewhere else but the neutral.

One should not (in some cases, cannot) cascade GFCI devices. Often this wil l cause false-trips, especially with motors.

A GFCI is also an ultra-fast circuit breaker. Meaning that older motors tha t commonly will not trip a regular breaker will often trip a GFCI, yet not be defective - this due to the momentary turn-on surge.

If a properly installed, properly functioning GFCI device is tripping - it is for a reason. As it is a life-safety device, the point of all this is no t to defeat it, but to correct the reason for the tripping.

Any other response is stupid. Any other advice is blather.

Peter Wieck Melrose Park, PA

Reply to
peterwieck33

And yet, we have people posting here, that consistently prove you can't fix stupid.

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Reply to
Fox's Mercantile

The clipper is a double insulated device and so only has two wires in the cord. Where does the current go? It doesn't matter which way the cord is plugged. It is not a polarized plug so I have tried both ways. Still, almost always when the clipper is turned off the GFCI trips. Could this be from back EMF from the motor winding? A power surge when the magnetic field collapses? I have looked some online for the answer and haven't found it yet. Thanks, Eric

Reply to
etpm

Here's the explanation I read, quite some time ago. It still makes sense to me.

A GFCI tries to accurately measure the imbalance in the current flow between the hot and neutral wires, and trip the breaker if a significant imbalance appears. The imbalance would (goes the thinking) exist if and only if there's a current leak from hot, to ground (bypassing the neutral return).

GFCI balance sensors are not perfect. They usually consist of something like a toroidal transformer, with the hot and neutral wires forming one winding, and a sense winding forming the other. Any imbalance between the hot and neutral wire current flows would induce a current in the sense winding, while (in principle) perfectly balanced and opposed hot/neutral currents would result in no net magnetic flux and thus no current induced in the sense winding.

The balance of these toroidal transformers is necessarily imperfect. The hot and neutral wire paths aren't identical, sometimes one is wound a bit more tightly than the other, and they aren't the identical distance away from the sense winding. Hence, there's some difference in inductive coupling within the transformer, and some difference in capacitive coupling between the two "balanced" wires, and the sense winding.

This imbalance tends to be worse at high frequencies where e.g. the difference in capacitive coupling makes a difference.

When a motor-operated device is switched off, and creates a switching arc due to inductive "kickback", the arc creates a burst of high-frequency energy (easily covering the AM band and sometimes going up to VHF). Even if the hot and neutral currents are perfectly balanced (and they may not be - there might be some capacitive coupling between the device and the operator's hand) the less-than- perfect balance in the current sensor can allow a small blip of current to be induced in the sense winding... and this can trip the GFCI.

If the device contains a snubber, this may not happen. A GFCI with a snubber/EMI filter at its output (and I suspect that some of these do exist) would be less vulnerable to this sort of false trip.

Reply to
Dave Platt

I just replaced the GFCI outlets in my house. I had a problem with triggering for no apparent reason with new GE ones. Replaced these with Levitons and haven't had one trigger randomly. The washing machine is connected to one and the electric lawnmower is connected to another.

Reply to
Chuck

In a previous residence I had an "outside" GFCI trip when using an electrice lawn mower --- when the mower was plugged into the still-coiled 75 foot extension cord (... about a 3 foot diameter coil). Uncoil the extension cord and it ran Just Fine. The inductive kick of turning on the motor was enough to "do it".

Jonesy

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Reply to
Allodoxaphobia

Any other advice is blather.

I beg to differ. Other responses are not necessarily stupid nor blather. Th ere are additional valuable points to be made that you did not include.

hat commonly will not trip a regular breaker will often trip a GFCI, yet no t be defective - this due to the momentary turn-on surge.

Again, I beg to differ. A GFCI is is not by design a circuit breaker. It do es not respond to sustained circuit overload conditions in a manner that pr otects house wiring -- which is exactly what a breaker is intended to do. P revent fires.

A friend recently called me, mystified, asking why the GFCI he'd just insta lled was not tripping under a 30+ amp load, it was a 15 amp GFCI. I told hi m..... it's not a breaker. It's designed to protect humans from shocks, not fires. In this case, I expect the eventual failure mode would have been ov erheated wiring resulting in a fire somewhere in the circuit.... not necess arily the GFCI.

My friend was trying to create a protected sub circuit in a garage, where t here was no access to the breaker, because it was in the house. I instructe d him to install a sub panel with breakers and GFCIs in the outlets -- or u se GFCI breakers. An expensive option.

Will some GFCIs trip (as per this thread) from momentary overloads? Yes, be cause switching inductive loads create a brief imbalance in the neutral. Si gnals out of phase, so to speak. Not from over current. Most will happily s upply excess current if the rest of the house circuit allows.

Typically, a long wire run to a motor, an extension cord for example, will aggravate the imbalance, adding inductance.

this happens DOES NOT make the GFCI device faulty. It makes the device faul ty

Again, I beg to differ. Nuisance trips are NOT necessarily indicative of a defective device. There are various motor start and stop conditions that ca n cause an imbalance (loading, inductance, stalls, voltage drop, even tempe rature).

GFCIs do fail in-elegantly. Some will refuse to trip. Others will trip too often, even under non imbalanced conditions. Better quality GFCIs will hol d up longer and fail to safety -- tripping too often rather than not at all .

Terry

Reply to
Terry Schwartz

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