wwhitney
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Re: questions about supplied 30 amp leaf 2018 EVSE

Sun Jul 29, 2018 7:58 am

EVDRIVER wrote:If you have a 240V Nissan EVSE it needs to be on a 50A 14-50 outlet with a 50A breaker by code in most municipalities of the USA

A 14-50 receptacle on a 40A circuit is more usual for a 30A EVSE and is NEC compliant.

Cheers, Wayne

jjeff
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Re: questions about supplied 30 amp leaf 2018 EVSE

Sun Jul 29, 2018 8:05 am

EVDRIVER wrote:
Solarninja wrote:Just my experiance...i ran a 30 amp dedicated circuit for my 2018 leaf yesterday...it tripped after about 10 mins of charging, so i grabbed my amp meter and flipped it back on
Image 31.4 amps... also very hot to the touch...i would HIGHLY reccomend 8gauge wire, 40 amp dedicated plug for charging these vehicles...especially in hot climates because they are obviously capable of drawing WAY more than the claimed 27~a i keep seeing thrown around on this thread


If you have a 240V Nissan EVSE it needs to be on a 50A 14-50 outlet with a 50A breaker by code in most municipalities of the USA and likely Canada as well. You should never have this EVSE on a 30A circuit and you really should hire a professional to inspect your wiring as it never should have been on the wrong circuit type.

By code a 14-50 outlet can be on a 40a circuit with 40a wiring, personally I'd label the outlet with a sticker that stated such though. Also a 40a circuit/wiring should be just fine for a Leaf charger, even if it drew 32a, it would be within the 80% rule. 30a is just too low though, even at 27.5a(which is what my '13S Leaf maxes out at) your wiring/breaker will get warm after extended use. I use such a setup at work for short-term charging but am very conscious about limiting my charging time, I wouldn't even to attempt charging if my Leaf approached 30a or more.
Whitney snuck in while composing my post, and of course he's correct :)
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Re: questions about supplied 30 amp leaf 2018 EVSE

Sun Jul 29, 2018 8:39 am

jjeff wrote:
EVDRIVER wrote:
Solarninja wrote:Just my experiance...i ran a 30 amp dedicated circuit for my 2018 leaf yesterday...it tripped after about 10 mins of charging, so i grabbed my amp meter and flipped it back on
Image 31.4 amps... also very hot to the touch...i would HIGHLY reccomend 8gauge wire, 40 amp dedicated plug for charging these vehicles...especially in hot climates because they are obviously capable of drawing WAY more than the claimed 27~a i keep seeing thrown around on this thread


If you have a 240V Nissan EVSE it needs to be on a 50A 14-50 outlet with a 50A breaker by code in most municipalities of the USA and likely Canada as well. You should never have this EVSE on a 30A circuit and you really should hire a professional to inspect your wiring as it never should have been on the wrong circuit type.

By code a 14-50 outlet can be on a 40a circuit with 40a wiring, personally I'd label the outlet with a sticker that stated such though. Also a 40a circuit/wiring should be just fine for a Leaf charger, even if it drew 32a, it would be within the 80% rule. 30a is just too low though, even at 27.5a(which is what my '13S Leaf maxes out at) your wiring/breaker will get warm after extended use. I use such a setup at work for short-term charging but am very conscious about limiting my charging time, I wouldn't even to attempt charging if my Leaf approached 30a or more.
Whitney snuck in while composing my post, and of course he's correct :)



Code varies in every municipality so 40A breaker is not code on all 14-50 outlets as a device that draws 40A would not be derated by 20%. You can't have a Tesla 40A continuous EVSE on a 40A breaker.
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wwhitney
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Re: questions about supplied 30 amp leaf 2018 EVSE

Sun Jul 29, 2018 12:19 pm

EVDRIVER wrote:Code varies in every municipality so 40A breaker is not code on all 14-50 outlets as a device that draws 40A would not be derated by 20%. You can't have a Tesla 40A continuous EVSE on a 40A breaker.

I'm not aware of any municipality whose written rules would disallow a 14-50 receptacle on a 40 amp breaker for a 32 amp continuous or 40 amp non-continuous load. That would be an odd amendment to make to the NEC. Can you provide an example?

You are correct that a 40A continuous EVSE should not be plugged into a 40 amp circuit, although if everything is installed correctly, the worst that will happen is that the breaker will nuisance trip.

If I recall correctly, older Tesla UMCs would default to 40 amps continuous when used with a 14-50 plug; if there was not an easy option to configure the UMC to 32 amps for the case of a 40 amp circuit with 14-50 receptacle, that was a failing on the part of Tesla.

Cheers, Wayne

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Re: questions about supplied 30 amp leaf 2018 EVSE

Sun Jul 29, 2018 1:26 pm

EVDRIVER wrote:
jjeff wrote:
EVDRIVER wrote:
If you have a 240V Nissan EVSE it needs to be on a 50A 14-50 outlet with a 50A breaker by code in most municipalities of the USA and likely Canada as well. You should never have this EVSE on a 30A circuit and you really should hire a professional to inspect your wiring as it never should have been on the wrong circuit type.

By code a 14-50 outlet can be on a 40a circuit with 40a wiring, personally I'd label the outlet with a sticker that stated such though. Also a 40a circuit/wiring should be just fine for a Leaf charger, even if it drew 32a, it would be within the 80% rule. 30a is just too low though, even at 27.5a(which is what my '13S Leaf maxes out at) your wiring/breaker will get warm after extended use. I use such a setup at work for short-term charging but am very conscious about limiting my charging time, I wouldn't even to attempt charging if my Leaf approached 30a or more.
Whitney snuck in while composing my post, and of course he's correct :)



Code varies in every municipality so 40A breaker is not code on all 14-50 outlets as a device that draws 40A would not be derated by 20%. You can't have a Tesla 40A continuous EVSE on a 40A breaker.

I believe the reason you can put a 14-50 outlet on a 40a circuit is that there isn't a NEMA 40a 240v outlet, outlets go from 30a to 50a.
2012 SL purchased used 2/'16
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'12 EVSEupgrade'd 20a L1/L2 EVSE, '13 EVSEupgrade'd adjustable 6-20a L2, 6-13a L1 EVSE
Zencar 13, 20, 30a L1/L2 portable EVSE
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davewill
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Re: questions about supplied 30 amp leaf 2018 EVSE

Mon Jul 30, 2018 9:58 am

EVDRIVER wrote:Code varies in every municipality so 40A breaker is not code on all 14-50 outlets as a device that draws 40A would not be derated by 20%. You can't have a Tesla 40A continuous EVSE on a 40A breaker.


I suppose nothing is absolutely code in EVERY municipality, but using a 50a receptacle on a 40a circuit for a 30/32a EVSE is a very common install method. It depends on the rating of the EVSE, which in the case of the Nissan is 30a, so a 40a circuit is fine. I would personally put in a 50a circuit if I had it to do again, but if you hand the Nissan EVSE to an electrician and just say, "install it" I bet they install a 40a circuit every time. Nothing wrong with that and there are many circumstances that would even make that desirable, like existing wiring, a long run where the cost difference is significant, or panel capacity issues.
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Re: questions about supplied 30 amp leaf 2018 EVSE

Mon Jul 30, 2018 10:55 am

davewill wrote:
EVDRIVER wrote:Code varies in every municipality so 40A breaker is not code on all 14-50 outlets as a device that draws 40A would not be derated by 20%. You can't have a Tesla 40A continuous EVSE on a 40A breaker.


I suppose nothing is absolutely code in EVERY municipality, but using a 50a receptacle on a 40a circuit for a 30/32a EVSE is a very common install method. It depends on the rating of the EVSE, which in the case of the Nissan is 30a, so a 40a circuit is fine. I would personally put in a 50a circuit if I had it to do again, but if you hand the Nissan EVSE to an electrician and just say, "install it" I bet they install a 40a circuit every time. Nothing wrong with that and there are many circumstances that would even make that desirable, like existing wiring, a long run where the cost difference is significant, or panel capacity issues.


Yes it is however there is no way to insure what is plugged into that outlet. I have seen more than one inspection failed for that reason. In some areas EV charging installations require special permits even when it's only a 240V outlet. Inspectors also make a call on site as to what they deem is ok. I have seen very liberal to insanely strict. Since a 14-50 is an outlet and not hard wired there is no way to determine what loads may be plugged in. In cases where a 50A circuit can be run it makes more sense, additionally tripping a breaker is not the only side effect of running a breaker at it's full value, the 20% rule helps keep connections from failing over time from heat, this is why there are special breakers with better connectors for continuous use at their full rated value. These are rarely used as it is easier to follow the general rules for derated circuits. I was just on an inspection this week and the inspector was so relaxed about everything and yet a month ago the guy went though every wire in the panel and even read every wire size, he almost failed the inspection for some sensor wires until he saw they were rated for 600V. Really depends where you live and who you get, fridays are good days to schedule inspections FYI:)
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wwhitney
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Re: questions about supplied 30 amp leaf 2018 EVSE

Mon Jul 30, 2018 11:58 am

EVDRIVER wrote:Inspectors also make a call on site as to what they deem is ok.

One does have to watch out for inspectors who make up their own rules. Unless the rule is adopted in writing by the jurisdiction, or a reasonable interpretation of the text of the NEC, it is not valid. If necessary, I would politely challenge an inspector who told me that I can't put a 14-50 receptacle on a 40 amp circuit.

EVDRIVER wrote:additionally tripping a breaker is not the only side effect of running a breaker at it's full value, the 20% rule helps keep connections from failing over time from heat, this is why there are special breakers with better connectors for continuous use at their full rated value.

Certainly continuous use will out any poor connections. But otherwise, the breaker is the only part of the circuit not rated for continuous use at100% of its rating. The 100% rated breakers you mention (breakers that can be used continuously at their full rating) prove this point: when using a 100% rated breaker, no other upgrades to the circuit are required to operate at 100% of the breaker rating.

To my knowledge, the differences between a 100% rated breaker and a regular breaker are primarily in the enclosure (and the enclosure is part of the 100% rating). I believe that the UL testing for any breaker requires it to hold at 100% of its rated current under test conditions, out in the open. An enclosure for a 100% rated breaker will hold only one breaker and will have been tested to ensure an adequate rate of heat rejection. That is a vastly different thermal environment than a load center, where multiple breakers are installed in close proximity, and where the 80% maximum continuous current rule applies.

For EVSE installations, 100% rated breakers are not available, as I don't believe anyone makes them smaller than 200A. Their value comes in larger installations, where the cost of the wiring dominates, and the savings from using a conductor at 100% of its ampacity outweighs the extra cost of the breaker.

Cheers, Wayne

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Re: questions about supplied 30 amp leaf 2018 EVSE

Mon Jul 30, 2018 12:10 pm

I don't know how many electrical inspections you have been on and how many times you have challenged and inspector but best of luck with that, it often does not end well. There are plenty of things inspectors push back on and why argue when it's so easy in this case to comply. I have 20 plus years of experience in residential construction and challenging an electrical inspector for something like this can lead to a job site nightmare. Been there, won't do that for a trivial matter like this that would run red flags al over the job or residence.
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wwhitney
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Re: questions about supplied 30 amp leaf 2018 EVSE

Mon Jul 30, 2018 12:22 pm

EVDRIVER wrote:I don't know how many electrical inspections you have been on

Maybe six? I could be off by one or two.

EVDRIVER wrote:and how many times you have challenged and inspector but best of luck with that, it often does not end well.

If your experience has been that it "often" hasn't ended well, and you've approached them politely, then I'm sorry that you are stuck with such bad inspectors.

Cheers, Wayne

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