Need Help with an electrical issue, please.

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glaudeja

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Yes it makes little sense and creates problems. (Most EVSE won't work with this setup so you have to hardwire them). However, like I said, the code is usually a response to a specific problem. In this case it's unlikely to have involved an EVSE or any other device which had a GFCI. But since you can plug any number of devices into an outlet, it's hard to make an exception. Though in fact this does occur with the requirement of a label stating that only X device can use the outlet, they just went ahead and required a GFCI. This no doubt solved the problem they were looking at but has created problems for EV charging.

The reason 40A breakers would be better than 50A is that they match the EVSE. While the saying is "the breaker protects the wire", it's also true that it protects the appliance.

I just noticed you are in Canada. Would the requirement for the 14-50 outlet even apply to you? As noted it's the rule in many but not all US jurisdictions.
The code in Canada specifically states that all EV chargers require a GFCI breaker installed.

" All single phase receptacles installed for the connection of electric vehicle charging that are rated 150 Volts to ground or less and 50 Amps or less shall have a GFCI".
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JCHLi

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The code in Canada specifically states that all EV chargers require a GFCI breaker installed.

" All single phase receptacles installed for the connection of electric vehicle charging that are rated 150 Volts to ground or less and 50 Amps or less shall have a GFCI".
Luckily my outlet was installed for a welder... The fact that it is used for EV charging is another matter.

So I take it they have adopted the latest NEC or do Canada make it's own electrical code?
 

DBC

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I know that my local code is that if it is garage circuit it does have to be GFCI protected. Have an electrician coming tomorrow to get a quote to get the circuit and plug installed for the mobile charger. Will eventually get a Juicebox or Chargepoint Flex to plug into it.
I suspect you're thinking of a 120v circuit. The GFCI requirement for 240v circuits is relatively new and isn't applicable in many jurisdictions.

Other than costing $50-$100 more, the only downside of having a GFCI protected circuit is tripping due to having two GFCIs on the circuit. That is not only inconvenient but it can also damage the breakers and the EVSE. Most manufacturers -- Clipper Creek, ChargePoint, JuiceBox -- say their units won't work with a GFCI breaker and require a hardwired unit. Hopefully the Ford mobile charger won't have this issue. That may be a TBD type thing.
 

DBC

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" All single phase receptacles installed for the connection of electric vehicle charging that are rated 150 Volts to ground or less and 50 Amps or less shall have a GFCI".
There you have it. Our gift from China/Amazon/Home Depot. LOL
 

Maquis

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First, let me say that I'm not familiar with the Canadian Electrical Code (CEC), and everyone who's answered so far is in the USA.

Beginning with the 2017 NEC, all receptacles installed in a dwelling unit garage must be GFCI protected. There is no exception for EVSEs. Not all states / local jurisdictions have adopted 2017 or 2020 codes yet.

The notion that a device with a GFCI will cause nuisance tripping if plugged into a GFCI-protected receptacle is urban legend (in other words, total BS). If a manufacturer's installation instructions state that the device should not be installed on a GFCI-protected circuit, I wouldn't buy that device. When they say that, what they are really telling you is "if your GFCI trips, don't call us, because we're not going to help you".

Example:
Every hair dryer, curling iron, etc. has a built-in GFCI on the end of the cord. Every bathroom receptacle installed per code in the US since the 1970s is GFCI-protected. If these caused nuisance tripping, no one would be able to do their hair! ?

There are devices made that will cause GFCIs to trip. 90% of them do so because they have cheaply-designed surge protection circuitry that cause leakage current top ground during normal operation.
 


Dnorwood98

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I suspect you're thinking of a 120v circuit. The GFCI requirement for 240v circuits is relatively new and isn't applicable in many jurisdictions.

Other than costing $50-$100 more, the only downside of having a GFCI protected circuit is tripping due to having two GFCIs on the circuit. That is not only inconvenient but it can also damage the breakers and the EVSE. Most manufacturers -- Clipper Creek, ChargePoint, JuiceBox -- say their units won't work with a GFCI breaker and require a hardwired unit. Hopefully the Ford mobile charger won't have this issue. That may be a TBD type thing.
The specs for the mobile charger do state GFCI recommended. I printed them out for my.

Just looked on Chargepoint Flex and they say a GFCI is okay as long as it is plugged in and not hardwired. Juicebox does recommend against GFCI breaker for plug in application.
 

willowma

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The specs for the mobile charger do state GFCI recommended. I printed them out for my.

Just looked on Chargepoint Flex and they say a GFCI is okay as long as it is plugged in and not hardwired. Juicebox does recommend against GFCI breaker for plug in application.
This is also driving me crazy. I bought a ChargePoint Homeflex and am going round in circles before installation on the GFCI issue. The Q&A on their site does say GFCI outlet is ok, but their installation manual says that they recommend hardwired only if a GFCI circuit is required for an outlet to avoid nuisance tripping. I would prefer an outlet, but unless I ca resolve this, am probably going to go with hardwired. Does anyone have it installed with GFCI on an outlet without it being a problem to charge a Mach-E?
 

DBC

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The notion that a device with a GFCI will cause nuisance tripping if plugged into a GFCI-protected receptacle is urban legend
This would be funny if not so misleading. Nuisance tripping with an EVSE on a GFCI protected circuit has been documented for over a decade. Well known problem. But if you want to call it an "urban legend" that's your prerogative.

Here is what an electrical company that installs EVSE has to say about the urban legend: "Most modern Electric Vehicle Supply Equipment (EVSE), or EV chargers, have built-in GFCI protection. When the unit is hardwired, there is no need for a GFCI breaker. If the unit is installed with a plug with a GFCI breaker, there can and will be faulty trips. The sensitivity of the breaker is higher than the EV charger, and the power draw from an EV charger can trip the breaker."

But hey, they're electricians who install EVSE. What do they know.

The specs for the mobile charger do state GFCI recommended. I printed them out for my.

Just looked on Chargepoint Flex and they say a GFCI is okay as long as it is plugged in and not hardwired. Juicebox does recommend against GFCI breaker for plug in application.
Yes the documentation for the Ford Mobile Charger recommends a GFCI protected circuit. As mentioned hopefully it works.

As for the Charepoint Flex: "I can confirm that a ChargePoint Home Flex EVSE will trip the breaker GFCI, about once a week in my case. I switched to a hardwired connection so it would comply with code." https://www.chevybolt.org/threads/gfci-on-home-receptacle.36923/

The nuisance tripping issues may depend on the sensitivity of the circuit breaker. I think I've seen that Square-D breakers are less likely to nuisance trip. No idea how true that is.
 

Maquis

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This would be funny if not so misleading. Nuisance tripping with an EVSE on a GFCI protected circuit has been documented for over a decade. Well known problem. But if you want to call it an "urban legend" that's your prerogative.

Here is what an electrical company that installs EVSE has to say about the urban legend: "Most modern Electric Vehicle Supply Equipment (EVSE), or EV chargers, have built-in GFCI protection. When the unit is hardwired, there is no need for a GFCI breaker. If the unit is installed with a plug with a GFCI breaker, there can and will be faulty trips. The sensitivity of the breaker is higher than the EV charger, and the power draw from an EV charger can trip the breaker."

But hey, they're electricians who install EVSE. What do they know.

Yes the documentation for the Ford Mobile Charger recommends a GFCI protected circuit. As mentioned hopefully it works.

As for the Charepoint Flex: "I can confirm that a ChargePoint Home Flex EVSE will trip the breaker GFCI, about once a week in my case. I switched to a hardwired connection so it would comply with code." https://www.chevybolt.org/threads/gfci-on-home-receptacle.36923/

The nuisance tripping issues may depend on the sensitivity of the circuit breaker. I think I've seen that Square-D breakers are less likely to nuisance trip. No idea how true that is.
I appreciate the feedback.

That quote from the electrical company is mostly correct, but has one portion that is fundamentally misleading. The statement that "the power draw from an EV can trip the breaker" doesn't say whether the trips are caused by GF detection or overload. Since power draw itself cannot cause a GF, they must be talking about overload. I suspect that this electrical company has experienced a significant number of nuisance trips with EVSEs on GFCI-protected cuircuits and simply assumed that the reason is that the EVSE includes its own GFCI protection without actually investigating the root cause.

The way a GFCI works it monitors the current of all current-carrying conductors - under ideal conditions, this should net to zero. If it's not zero, the difference has to be the result of current flowing to an unintended path to ground. Once this value reaches a predetermined threshold, the GFCI trips. The (properly-designed) GFCI itself does not cause current to flow to ground so it will not trip other GFCIs on the circuit.

I'll reiterate that the reason most devices cause GFCIs to nuisance trip is due to the design of their built in surge protection. It is common for surge protection schemes to have metal oxide varistors (MOVs) conected from line to ground. When a voltage surge occurs, the MOVs try to limit the voltage rise by shunting current to ground. This shunt current is exactly what the GFCI is detecting causing the trip. Over time, the MOVs can become 'leaky' constantly shunting a small amount of current to ground which may or may not hit the threshold of GFCI protection. I believe this is what's the likely cause of EVSEs that trip GFCI breakers.

GFCI breakers can be sensitive to factors that should not cause them to trip. Many people with a pool pump powered by a VFD have experienced this. Pentair currently only recommends a specific Siemens GFCI breaker for use with their VFD pumps. There have been reports of ham radio operators being able to trip GFCIs while transmitting. An EVSE is a pretty simple device and should not emitting harmonics (like a VFD) or radio frequencies.

I'll also agree that different breaker manufacturers seem to be more immune to nuisance tripping (see Pentair example in last paragraph). My experience with Square-D QO line is that they are quite good. These are what I use in my home and shop. I know electricians who have reported more problems with Square-D "Homeline" (their cheaper line).
 

OldEVGuy

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Juicebox does recommend against GFCI breaker for plug in application.
Where I live, code requires GFCI to pass inspection. I asked Enel-X about it, before having a JuiceBox 40 installed last year. Here’s the response I received:

We understand certain state electrical codes require GFCI breakers so the JuiceBox can operate with these types of breakers. We simply recommend against them if possible. If it's not possible in your state, that's fine.
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