GM Volt Forum banner

GFI tripping and warm?????

22K views 35 replies 18 participants last post by  solar_dave 
#1 ·
For the second time in the last month the GFI in my garage tripped while our Volt was charging (OEM 120V charger).

The house is 7 years old and up to code. I do have a 25 year old side by side refrigerator plugged in as well. The GFI was VERY WARM to the touch as I went to reset it. It wasn't HOT and untouchable, but very warm.

Aside from the obvious (replacing the GFI) what else should I look for/at????
 
#2 ·
A dedicated circuit would be a better option. You shouldn't have two largish loads on the same circuit.

Since it's not popping the breaker, I'd have an electrician peek at ground and neutral for issues.

Personally, I would not use GFCI circuit for Volt or refrigeration, but, NEC says GFCI is 'required' in garage and bath and bedroom and kitchen and outdoors. <sigh>. We are overly governed imho.
 
#3 ·
Yeah. I'd say the easy thing to do here, is make sure you don't have two things plugged in at the same time. If it's safe, as you don't use anything else on that plug, and if the wire is adequate, get a 20amp plug so that you reduce some heat and wear. I think that would work great. You don't really need GFI as, that is what our EVSE's are.
 
#4 ·
For now I've set the charger to the lower setting, I'll pull the GFI tomorrow in daylight (after throwing the main breaker). But to test things I did unplug the fridge and plugged in the Volt. Within 5 minutes it tripped again.

More to follow I keep suggestions coming as I'm not an electrician.
 
#6 ·
I'm not either but maybe try a different outlet in the garage. My washer dryer are on a 20 amp circuit and no way the Volt level 1 charger can trip that.
 
#7 · (Edited)
While you have it out for inspection, also see if the wiring was pushed into the GFI back rather than attached to its side screws. Side screw attachment results in less resistance (heat). Warm is not unusual, too hot to touch would be cause for concern.
 
#8 ·
You have two separate issues here: 1) tripping the GFI, 2) resistance heating. The GFI (or GFCI if you prefer. Both terms work...) is not a current limiting device, it will not trip even if you pump 30 amps through it. This is a common misconception about GFI outlets. It will only trip under 2 conditions: 1) GROUND and NEUTRAL connect. 2) HOT and NEUTRAL have a load difference of 5 milliamps. It is not unusual for refrigerators to trip GFIs because the coils of the motor cause a brief delay in the energy returning down the neutral wire. Since you unplugged the fridge and still had the GFI trip, that's ruled out. Since your house is only 7 years old, it is highly likely that you have a 20 amp circuit in the garage. If this is true, Stevereno's suggestion about back-wired plugs shouldn't be an issue. It is not legal or physically possible to insert a 12 AWG wire into the holes used for 15 amp back-wired plugs.
I would suggest taking the easiest fix first: Buy a new 20 amp GFI and install it with wrapped side wired connections. If that doesn't get you working, post back for more help.
 
#9 ·
OK this is scary, removed outlet and this is what I saw


So I replaced it with a brand new 15AMP GFI and all is operational - for now.

So the question is what happened?? I have just two items on this circuit (wall outlets in my garage) a 25 year old GE side by side refrigerator and the Volt using the OEM charger running 120V at 12AMP's. Does anyone know how many AMP's a fridge like this can draw? Am I really overloading the circuit to cause this?

We'll probably move or get rid of the fridge, but is there a chance the GFI was "defective"?

Thanks for all your tips and advice.
 
#17 ·
So the question is what happened?? I have just two items on this circuit (wall outlets in my garage) a 25 year old GE side by side refrigerator and the Volt using the OEM charger running 120V at 12AMP's. Does anyone know how many AMP's a fridge like this can draw? Am I really overloading the circuit to cause this?
Here are a few details that may help understand:

A typical household circuit for outlets is 15A or 20A (I'd guess 20A for a newer house); it also may cover several rooms (e.g. in our house the garage outlets are on the same circuit as a bathroom, so they can share the same GFCI in the basement).

The Volt draws 12A (1,440W). That leaves 3A (360W) in a 15A circuit, or 8A (960W) in a 20A circuit. Basically, the electric code is saying "You're welcome to have a Volt, but if you don't have a dedicated circuit for it, be careful what else you have on the circuit." According to EnergyStar, a typical fridge of that era averages 250W. But they also show a fridge as typically using 750W when it is on, since it cycles on and off.

So a 25 year old fridge may well be closing in on (or over) the 960W that you likely have to play with. And that's assuming nothing else is on that circuit. And most household electrical outlets only use near-peak amps for relatively short periods of time, whereas this one would have the Volt using 12A for up to 10 hours straight. So yes, you really might be overloading the circuit with just the Volt and a fridge.

If I were you, I'd get a dedicated circuit installed (I paid about $150 for mine, and the electrician set it up with wiring that could handle 220V so it would be relatively simple to switch it to 220V later). My next choice would be separating the loads to two circuits (as you have done now); the last choice would be the 8A option (that would likely exceed 15A combined with the fridge).
 
#10 ·
Well, two things. I would try to get a 20 amp outlet so you have a bit of extra leeway, GFI really isn't necessary. The other issue is, I really hope you aren't running the fridge on the same circuit. The only way that is going to be safe is if you charge at 7 amps. A fridge can draw a lot of power, and your car is already drawing the maximum amount for that circuit.

It looks to me like that GFI feeds your refrigerator outlet as well. Since the car draws 13 or whatever amps, and your fridge can draw many amps, it's over the max.
 
#11 ·
Looks like the wiring was being asked to handle more current than it could and was overloaded. As you already know, the Volt needs a dedicated circuit, not shared with any other device. A refrigerator can pull some juice. This is likely one reason why GM decided to default the 2013 to 8 amps instead of 12.
 
#12 · (Edited)
UPDATE # 2

When I turned off the circuit breaker in the main panel for the wall outlets in my garage I noticed the garage door openers were still operational. So I went back and checked my main panel and sure enough my garage door openers are on their own separate circuit.

So to allow us to sleep at night until we can either install a dedicated 240V circuit for the Volt or get rid of the fridge, I split them up by plugging the Volt into the ceiling outlet on my third bay door opener. Right now it's not pretty, but safe and functional.


Tomorrow I'll tidy up the 15 foot extension cord I used.

WOW what a strange few hours this has been.
 
#13 ·
The breaker should have blown before the receptacle got that hot. The breaker in the panel might not be functioning properly.

Your fridge and volt would certainly overload a 15amp circuit if both were running. If it is in fact a 20amp circuit then it would be borderline but the breaker should still have popped. For safety, I would consider replacing the breaker on that circuit which should only cost $10 or so if you do it yourself. If the circuit has any chance of getting wet or devices connected to it get wet in any way then a gfi is a must.
 
#14 ·
The first and second time the main panel breaker tripped, the third and last time the GFI tripped. And yes I'll replace that breaker, thanks for the tip.
 
#15 ·
I would suggest reversing which load you run on the extension cord. Your fridge is probably pulling 4-6 amps and cycles on and off. That's the better load to run on an extension cord. On that pic you posted, it looks like you had push-in wires. If that is true, it tells me that you have 14 AWG wires and a 15 amp circuit breaker. Is that correct? Did you do wrapped side wiring for the new outlet? That alone should fix the resistance heating problem that melted down the old outlet.
 
#16 ·
I would suggest reversing which load you run on the extension cord.
I was thinking the same. Plug the fridge into the garage door opener outlet, and dedicate the wall outlet to the Volt. Maybe even plug one of those plastic child resistant caps into the other outlet in the receptacle just to prevent someone from accidentally plugging into the empty socket.
 
#19 · (Edited)
Those hole things are a crime. Probably would not had got warm at all using the screws, as things like wall sockets have high overhead tolarances these days for safety.

Most 15A circuits can easily be upgraded to 20A "T" plugs that you can plug normal 15A items into as well as wire gauge is normally more than sufficient but older NEC being 15A and all.

Personally 20A should had been the standard for wall sockets all along. 15A (12 max) just isnt enough these days....

The amount of wattage 230V standard countries can get out of a single standard wall socket is insane.
 
#20 · (Edited)
I'm an engineer in the wire and cable business.

One of the products my company makes is sealed circuit breakers for explosive gas environments. We don't make the breakers but we make the sealed enclosures. So I know a few things about circuit breakers and GFCI's. We also make many contrloller's with built in GFCI's.

1. Circuit breakers all have a wide range of calibration. They are not a precise device at all in any way whatsoever. When we make some of our products we have to check each circuit breakers calibration because they behave different in an enclosure. Under UL and CSA standards a 15A circuit breaker loaded to 16.5A can take up to 7 hours to trip and this is still considered a pass (A 15A breaker can also take 20.25A for up to 1 hour or 30A for 2 minutes and still be a pass). Most residential breakers are a thermal circuit and their sensitivity can vary a lot.

2. Under the code you cannot load a circuit breaker above 80% of its maximum rating. So with the Volt set to 12A under the code this must be a dedicated 15A circuit. If it's not a dedicated circuit use the 8A setting. A typical fridge can have a start up current of ~10A and then settles to a continuous current of ~3.5A.

3. GFCI's work by measuring the current in on the live (live 1) and compared to the current out on the neutral (live 2) lines (brackets are 240V/208V split phase). On a class A GFCI if the current is different by more than 5mA (0.005A) the GFCI will trip [this is called leakage current]. Sudden surges of current can trick a GFCI into tripping. Electric motors, compressors (like a fridge) and the like have been known to cause false tripping of GFCI's. That is why most fridges are on dedicated non-GFI circuits.

4. This is not directed at you but in general. A short circuit will not necessarily cause a GFI to trip (as current in will still match current out in a short). Here the breaker still becomes your fall back. The GFI looks for leakage (IE person getting shocked or a fault to the ground) and not a short circuit. SO DON'T OVERSIZE YOUR BREAKER. Because if you do and you get a short you could cause serious damage.

P.S. most European 230V residential circuit breakers (with recepticals) are 10A. Like our 120V 15A receptical.

Also many products limit themself to 12A continuous current or 15A maximum . Because if you go above 12A you then have to certify your products for 20A circuits. The certification requirements for a product designed for a 20A circuit are very different (and much harder) from one that is designed for a 15A circuit.
 
#22 · (Edited)
Let me circle back and try and answer some of the questions posed in numerous replies.

1. Originally since I bought my 2012 Volt I had both the Volt and a beer fridge running on the same circuit in my garage. DUMB.

2. Everything ran fine for 7 months, but early in Nov the car horn started beeping late one evening and that tripped the breaker in the main panel. I did notice the GFI in the garage was warm but not HOT. So I pressed on.

3. Yesterday the car tripped the main breaker a second time, I reset I and inspected the charger, cord and the wall outlets in my garage. Again the GFI was warm, but not HOT. When it tripped again I decided to pull the GFI and you saw what it looked like in one of the photo's I posted. Hence this post.

4. Where am I now/today.

A. I discovered my garage door openers are on a circuit all by themselves. I threw the breaker in the main panel and no other outlets are one it, so I bought a short 6 foot heavy duty extension cord to connect the Volt's charger to one of the garage door openers outlets in the ceiling.

B. The fridge is on the wall outlets in the garage that I originally had the Volt charing from, to test my theory I threw the breaker on the main panel and the only thing on this circuit are the outside outlets and the 5 wall outlets in the garage. The fridge is now on this circuit all by itself, unless I plug something into one of the outlets.

C. I did switch the charger to the lower setting (8 amps) for the time being. The longer charging times should have little impact on my driving routine.

We are going to be gone on a cruise attending my daughters wedding and will be back on Dec 15th. At that time I'll start getting estimates on dedicated 120V and 240V outlet(s) to future proof my garage since we are considering adding either a second Volt or Cadillac ELR.

So that's how things stand righ now.

Thanks to everyone that replied and offered up all their expertise and advice. I/WE learned far more about electricity and the Volt than I had hoped. I hope other Volt owners can benefit from this thread.

Cheers
 
#36 ·
We are going to be gone on a cruise attending my daughters wedding and will be back on Dec 15th. At that time I'll start getting estimates on dedicated 120V and 240V outlet(s) to future proof my garage since we are considering adding either a second Volt or Cadillac ELR.

So that's how things stand righ now.

Cheers
If you are going to add wiring to the garage consider running a sub panel in the 60amp range to the garage and really future proof your installation. It will only cost slightly more to have a line pulled to the garage and a sub panel added to allow a pair of 30 amp chargers to be connected locally.
 
#23 ·
First of all, glad you found the outlet problem. That could have been a disaster. Great you found it before anything untoward happened!

I think you're in good shape Tom. It seems you have two issues. One is the burned GFCI and the other is having both the fridge and the Volt on the same circuit.

I suspect that the burned GFCI is the result of the backstap connections. Lots of issues with these. They can work just fine -- they are UL approved -- but sometimes there are issues if people are working fast and there are lots of possible points of failure. A good quality outlet and side-wrapping the wired should fix this, as has been suggested. I also wonder if you need a GFCI. The EVSE has a built in GFCI.

Having the garage door opener and the Volt EVSE on the same circuit should not be an issue. The garage door opener is quite different than the fridge. The chances of having both the EVSE and the garage door running are probably very low, even they are it won't be for a very long time. Consequently if you want to keep the other garage outlets "EV Free" the cheapest solution would be to extend the garage door outlet to a second outlet for the Volt. That should be very easy to do. (That's what I did BTW).

Just as a note on the fridge: Older refrigerators are very inefficient and it can be very expensive to run them. Very expensive. The thing may be costing you $500/year, especially if the garage gets hot in the summer. If you do get rid of it you may see your electric bill drop.
 
#24 ·
In the NEC, permanent loads (like garage door openers) do not require GFI.

I charge my Volt from my garage door circuit (via a heavy-duty extension cord to the overhead outlet). The trick is not to have both loads on at the same time. I open the garage door twice a day: In the morning (when the Volt is fully charged and not drawing much current), and in the evening when I come home (when the Volt is not plugged in).

I agree with the consensus that the burned outlet problem was likely a cycle of resistive heating, corrosion, more resistive heating, more corrosion, etc. due to the through-hole / lazy-man's connection to the outlet. Screwing the wires down should prevent a recurrence. After some scary events, I went through every outlet in my house and replaced the cheap junk with spec grade outlets, and I screwed all of the wires down. A few bucks of savings is not worth a fire.

Also, please do not put a 20 A GFI outlet behind a 15 A circuit. The 20 A outlet allows the "T" connectors from 20 A-rated loads to be plugged in. While the 15 A circuit breaker will theoretically trip under 20 A load, why risk a fire (which wouldn't be covered by insurance due to the code violation) due to overheated 14-gage wiring behind the wall?
 
This post has been deleted
#25 · (Edited)
I worry about that also. GM could satisfy their lawyers by not recommending plugging the car in at all, but at some point, they need to consider customer satisfaction. Having to configure the charging mode *every* day is a burr under many customers' saddles. In my opinion, a good compromise would be the following:
* 120V charging defaults to 8A / slow charging.
* Once the customer sets it to 12A / fast charging, it stays that way until either the customer changes it back, or charging is interrupted unintentionally (i.e., presuming a popped circuit breaker).
* If they wanted to get fancy, they could make it location-aware (using cellular tower triangulation and/or GPS) such that the fast charge setting would remain in effect until the customer sets it back to 8A, charging is interrupted, *or* the car is in a new location.
 
#27 ·
"ell, maybe next year, they'll go to a 4A default "

actually according to old posts : 6 amps is as low as the current in car charger will go via the pilot pin.
-----

I charger my volt in a 120 volt circuit shared with 6 other garage door openers each with their own socket but same breaker. I do use 8 amps as once in the last year three people opened at the same time when I was using 12 amps.
 
#29 ·
FYI my garage door openers are not on a GFI, not sure how that got into this thread. It was the wall outlets installed in the walls that are GFI protected and that GFI was fried.
 
#30 ·
My GFI trips about 20% of the time when I plug in the Volt for a 110 low amp charge, just like when I plug in power tools outside to the garage 15 amp circuit. It seems like there is a static issue or something when I push the plug in. Now when I plug the connector into the Volt, I keep the button held down for 5 seconds before I release (give time for any grounding or static electricity to dissipate or something). This seems to work and when I do this and I don't trip the GFI. However, I've only been doing this for about a week, so time will tell. I do have a freezer in the garage and can hear when it is running. When I do trip the GFI, it doesn't seem to matter if the freezer is running or not. So I've been playing this game for about 2 months since I bought the Volt. This would be very annoying to some people, but it's no big deal to me.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top