70 amp circuit 50 amp recept. gfi?

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ritelec

ritelec

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Hello, I may be installing an EV charger requiring a 70 amp circuit to a garage to a 50 amp receptacle for a car charger.
We are still using 2017 so I believe gfci is not required. Confirming that 2020 would require that receptacle to be gfci protected even if on a 70 amp circuit. Correct? Thank you.
 
Branch circuits greater than 50A serving EVSEs must be hard-wired. Receptacle is not permitted.

Besides, I don’t think you can install a single 50A receptacle on a 70A branch circuit in any case.
 
Interesting. The direction booklet had 50a receptacle requiring a 70 amp circuit. and this is the male plug on the cord.

I figured 50 x 125%= 62.5 would put it on the 70 as the directions said. Please sight code for not greater than 50 amp hardwired and 70 on the 50 receptacle please. I will look also.
Thank you.
 

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thank you. I remember the welder exception.
What to do if the directions said 50 amp max, 70 amp circuit? And has a factory plug like this on it ?
 
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ritelec said:
What to do if the directions said 50 amp max, 70 amp circuit? And has a factory plug like this on it ?
Click to expand...
If the manual allows it, you can hardwire it on a 70A circuit. Otherwise, you need to use a 50A circuit, a 14-50 receptacle, and to program it (e.g. via dip switches) for 40A max continuous current. And if it can't be so programmed and can't be hardwired, it has been misdesigned and is unusable.

Got a pointer to the product/manual?

Cheers, Wayne
 
These oversizing of breaker compared to wire/devices if I'm correct are usually only involved for accommodation of short duration/surge loads related to motors and the like. A long or continuous load like that of an EV charger at that capacity could burn out the lower rated wiring/device and be a fire hazard.

As Wayne eluded to, if instructions so stated the installation, I might also question it and also validity of its listing (if even having one).
 
Thank you. I’ll see about checking out that charger again today.

I’m concerned now 625.44.
actually 625.43...

I recently hard wired a 48 amp Tesla charger on a 60 amp circuit.

There is no disconnect at the charger location. Just the circuit breaker at the main panel.

For portable you would have the receptacle as the disconnect. For more than 60 amp (625.43) a readily accessible disconnect is required.
For a 60 amp charger, is no disconnect required ?
Not even a lock out for the panel
breaker ?

thank you
 
IMO, since it does not say readily accessible TO THE CHARGER, a readily accessible breaker with a locking mechanism in the panel would meet Code.
 
UL2594 requires the attachment plug of an EVSE to be rated at 125% of the unit’s maximum current. So the device you’re installing cannot be more than a 40A device if it came with that plug. A 50A branch circuit would be sufficient.

Presuming it’s UL listed?
 
There is no requirement for a disconnect on units 60 amps or less. IMO, if you wired it for 60 amps than you are fine. I haven't checked the 2020 nec yet
 
The 2020 does not require it either but be careful reading this section.

625.43 Disconnecting Means.

For equipment rated more than 60 amperes or more than 150 volts to ground, the disconnecting means shall be provided and installed in a readily accessible location. The disconnecting means shall be lockable open in accordance with 110.25.
Click to expand...
 
Ok. Thank you.
To me it doesn’t look like it requires a lock out either on the breaker.
It wouldn’t hurt to put one on, but am I reading that correctly?
This stuff gets me doubting everything I do.

We are using the 2017.
Now I’m doubting if it should be on a gfci circuit.
In 2020 receptacles and outlets 50 amp and under need gfci protection.
But I don’t see any mention of that in the 2017. This Tesla 48 amp is on a 60 is NOT gfci protected. For 2017, that would be correct right? ( please confirm )

If we were using the 2020. That Tesla 48 amp unit on a 60 amp breaker ... would it require gfci protection because it’s an outlet
under 50 amps ( 48 amps ) or not require gfci protection because it’s on a 60 amp outlet ( circuit )

1) lock out required on circuit breaker?
2) Gfci required? 2017
3) Gfci required? 2020

Thank you for helping me get my head around this.
 
Ok, I opened the book quickly yesterday and went to the first page that had grayed line amperage 50 max and circuit 70, and figured that was it without looking through the rest of the booklet.
So I'm guessing this unit is the 50amp model.
As stated before, in 2017 I don't see that 50 amp receptacles need gfci protection in garages,
and these directions say they DON'T want it plugged into a gfci protected circuit.
If I did need Gfci protection (2017), and 2020 you have to have gfci, what do you do? Cut the factory end off and wire it to a disconnect with no gfci protection? Wouldn't that be an outlet anyway and require GFCI?

Thank you
 

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So you have Chargepoint Home Flex, the manual is available here: https://www.chargepoint.com/resources/chargepoint-home-flex-cph50-installation-guide.

See page 17--that indicates that there is a software commissioning step at which point you program the charger for the maximum (continuous) charge rate, from 16A to 50A, with it defaulting to 16A. So the unit can be installed on a circuit of any size from 20A to 80A, hard wired or cord and plug connected. [It may come with a cord, but the manual has instructions for hard wiring.] Cord and plug is obviously limited to 50A for standard NEMA receptacles. And the unit's continuous charge rate is limited to the lesser of 50A or 80% of the circuit rating.

As to the comment in the manual about not putting the EVSE on a GFCI, that's probably incorrect. If the unit doesn't do any ground assurance testing that intentionally puts current on the EGC, then there's not problem with having ground fault detection in series. If the unit uses ground fault detection but at a higher trip level than a GFCI, then obviously putting it on a GFCI will cause the system to trip sooner, but that's what the 2020 NEC requires in many cases.

If the unit does incorporate ground assurance testing that intentionally puts current on the EGC, and it puts more than 4ma on the EGC during that test, then it will need to be redesigned for compliance with the GFCI requirements. Or I believe you could hardwire on a 60A or larger circuit, and then GFCI would not be required (under the 2020 NEC).

Cheers, Wayne
 
Thank you. I’ll look into that manual.
It comes wired up with that 50 amp plug.

the owner sent me those Booklet pictures

you would think if the plug was on it you would just plug it in and be ready to go.
 
ritelec said:
Ok, I opened the book quickly yesterday and went to the first page that had grayed line amperage 50 max and circuit 70, and figured that was it without looking through the rest of the booklet.
So I'm guessing this unit is the 50amp model.
As stated before, in 2017 I don't see that 50 amp receptacles need gfci protection in garages,
and these directions say they DON'T want it plugged into a gfci protected circuit.
If I did need Gfci protection (2017), and 2020 you have to have gfci, what do you do? Cut the factory end off and wire it to a disconnect with no gfci protection? Wouldn't that be an outlet anyway and require GFCI?

Thank you
Click to expand...
I've done these in Tesla before. 50A max is breaker size, circuit 70 amp is conductor size. (From Tesla instruction wording)
This unit you showed also has hard wire optional. I would go that way myself.
 
ritelec said:
you would think if the plug was on it you would just plug it in and be ready to go.
Click to expand...
You can, with a 14-50 receptacle and a 50A circuit, and then the initial commissioning just has to be for a 50A circuit/40A max continuous current, rather than anything higher.

Cheers, Wayne
 
Thank you. I let the owner know that I will run a 60 amp hardwired circuit to it if he wants. No gfci. No disconnect 😁
 
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