Nissan EVSE J1772 cable wire gauge?

I think I read a post somewhere, saying that Nissan had cheaped-out on later-model EVSEs, and started using thinner wire gauge from the J1772 to the EVSE. Does anyone recall if that's correct, and what year?

My J1772 cable (from 2017 Leaf) gets pretty warm, just charging at 12A... warm enough to melt through ice. If the ice re-freezes, then you end-up with a J1772 cable under a quarter-inch of ice, and it's very hard to get the cable free without using an ice chipper.

It was 2015 model year that Nissan cheaped out and switched to 14 gauge wire(note not as bad as some other mfgs. that use 16g J1772 wire!) but none the less doing so EVSEupgrade was no longer able to make the upgrade to 20a but had to max out at 16a(maximum rating for 14g wire). Note 16g wire is capable of 12a or what some EVSEs top out at but due to heat loss, the smaller the gauge(even if still within the maximum limits) the less efficient it is. Personally, I don't want to waste electricity heating up the already too warm earth
http://evseupgrade.com/?main_page=index&cPath=1&zenid=nbbjck0lck7keql8v5si1snio7

Unfortunate that they started doing that to the wires in 2015. Does it have the same issue on the 2018 model?

I'm not a EE, but it seems to me that one of the important safety considerations for wire choice is flexibility (or whatever the precise term for resistance to damage due to flexing). Since a charging cable needs to be able to withstand what may be considerable flexing over time, a thinner multi-strand wire should maintain its integrity longer than a thicker one subjected to the same usage abuse. In any case, I recommend everyone treat (any) cable subject to flexing during normal use with appropriate due care.

Flexibility is more related to the gauge of the individual strands of wire that make up the total wire. IOW a cheap wire will have very few strands but each strand will be thick, a better more flexible option would be very fine strands but very many of them. Of course if you live in colder climates like mine, the material of the jacket makes a big difference. A more rubbery jacked will remain flexible even in sub zero(F) temps while a vinyl or plasticy jacket will start getting stiff as it gets below about 40f and become basically worthless below zero F.

Just installed my Clipper Creek, it uses 10ga wire for the three main leads, and 18ga for the pilot signal.

From your wire gauge it is a 30A unit. Maybe pushed to 32A.

10 gauge wire is good for at least 30A but in an enhanced 2013 unit it will only draw 27.5A. A basic S will draw 16A. Same for a 2011 or 2012 Leaf.

Remember that an EVSE that is designed to be "portable", i.e. capable of being stuffed (preferably carefully coiled!) into a smallish bag (and again and again and again!) and relatively light-weight has to be designed differently than non-portable EVSEs. It makes much more sense to make comparisons of this EVSE with other portable EVSEs -- or at least point out if a comparison EVSE is not portable.

If you intend to mount an EVSE permanently, say on a wall, then it is better (safer) to buy an EVSE designed for that purpose -- and to have it DIRECT WIRED! If you have two Leafs but not the electrical capacity to charge them both at the same time, then a reasonable solution might be having two differently located 14-50R receptacles (together with an EVSE holder underneath like the one that comes with this EVSE) and alternating this portable EVSE between the two of them for charging each Leaf (rather than moving each Leaf to the single EVSE charging point). Make sure that you follow 2017 NEC code and have a GFCI breaker for each circuit!

BTW Clipper Creek is currently one of the few EVSE vendors that sell an EVSE (having their Share2 option) that can be paired with another similar one in which a communication wire runs between them for the purpose allowing only one charge at a time -- great for houses with electrical service only sufficient for a single charging session. Note: Unfortunately, I believe that this option currently can't be added to an existing CC EVSE.

The problem with hard wiring an EVSE is that the whole thing is inspected. By adding a 14-50 recptical is that is where the inspection stops. My panel and wiring was inspected but my OpenEVSE was not.

GlennD: Fine -- at least acknowledge the value towards safety of an upstream GFCI protecting that receptacle! And also acknowledge known safety deficiencies (if any) of the "Open" EVSE versus, say, the EVSE of this post.

BTW I make posts on MNL to try to provide Leaf owners with information that I hope they will find useful, especially about charging issues that involve safety -- but I am hardly perfect in that regard. I do not have a personal financial stake (or have friends who do) in selling EVSEs that ends up affecting what I write. I feel strongly that "good" information helps people make better choices, but it is a struggle (and expense) to find that information -- and it can be difficult to communicate it effectively.

MikeD said:

I'm not a EE, but it seems to me that one of the important safety considerations for wire choice is flexibility (or whatever the precise term for resistance to damage due to flexing). Since a charging cable needs to be able to withstand what may be considerable flexing over time, a thinner multi-strand wire should maintain its integrity longer than a thicker one subjected to the same usage abuse. In any case, I recommend everyone treat (any) cable subject to flexing during normal use with appropriate due care.

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Quick Charge power like Tesla uses doubled up wires for their 40A cable. This makes it very flexible and it is smaller than most 30pA cables. I use one for its 40A capability but since it is smaller than the old 30A cable that they used to sell they dropped it and now only sell the 40A J1772 cable.

GlennD: Isn't there a danger in using "double wiring" (if I am correctly understanding you mean two separate wires are used for part of a circuit instead of just one) that the current can rather easily become unbalanced between the two wires? As an example, if a total of 30a is passing thru the two wires, assuming the wires have initially exactly the same total resistance, then 15a passes thru each wire. But if one (wire A) degrades differently over time such that it eventually has, say, twice the total resistance of the other (wire B) then the current flowing thru wire B will be twice that of wire A, i.e. approximately 20a versus 10a -- i.e. isn't there the very real possibility of eventual heat damage to wire B's insulation? Or am I misunderstanding something?

MikeD said:

GlennD: Isn't there a danger in using "double wiring" (if I am correctly understanding you mean two separate wires are used for part of a circuit instead of just one) that the current can rather easily become unbalanced between the two wires? As an example, if a total of 30a is passing thru the two wires, assuming the wires have initially exactly the same total resistance, then 15a passes thru each wire. But if one (wire A) degrades differently over time such that it eventually has, say, twice the total resistance of the other (wire B) then the current flowing thru wire B will be twice that of wire A, i.e. approximately 20a versus 10a -- i.e. isn't there the very real possibility of eventual heat damage to wire B's insulation? Or am I misunderstanding something?

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You might think that, but it's done all the time in high current situations
It one of the commercial buildings I work at for the main feed wire they had like 6 wires for each of the phases, 24 very heavy wires in total :shock:
I believe how it works is as long as the wires are similar in size the current will balance between the wires, if say one wire gets a bad connection and starts heating up, it's resistance goes up and current is routed through the other wires(a good thing) as without the other wire/wires, the wire would keep getting hotter and hotter, possibly resulting in a fire or melting of the bad wire.
Whitney probably knows the code but I believe for smaller gauge house wiring, your not allowed by code to double up the wire, things that are plugged in like a EVSE probably go off a different code.

MikeD said:

GlennD: Isn't there a danger in using "double wiring" (if I am correctly understanding you mean two separate wires are used for part of a circuit instead of just one) that the current can rather easily become unbalanced between the two wires? As an example, if a total of 30a is passing thru the two wires, assuming the wires have initially exactly the same total resistance, then 15a passes thru each wire. But if one (wire A) degrades differently over time such that it eventually has, say, twice the total resistance of the other (wire B) then the current flowing thru wire B will be twice that of wire A, i.e. approximately 20a versus 10a -- i.e. isn't there the very real possibility of eventual heat damage to wire B's insulation? Or am I misunderstanding something?

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The quick charge cable has 2 #12 wires on each side. Each wire is good for 20A thus the total assuming the wires are terminated properly is 40A. I charge my "B" at 40A with no problem from a 63A contactor.

I earlier tinned the wires It needs the contact area of non soldered wires, WRONG! It is the only contactror that I have blown up. It was a 50A unit running 30A. Properly terminated it had a lot of reserve.

jjeff: Your comment about the NEC disallowing double wiring is correct, I think (but I haven't tried to research it).

However, I believe your comment "if say one wire gets a bad connection and starts heating up, it's resistance goes up" is not consistent. When wire A gets "a bad connection" its effective resistance goes up right then, causing less current to flow thru it and more to flow thru wire B, with the net effect being wire A immediately starts cooling off (assuming no arcing is also occurring) and wire B starts heating up -- and the concern is eventually maybe to insulation damaging levels.

In your industry example, it's not just two wires but six, so a high resistance defect with one wire causes its current to be shared among the remaining five rather than just one. Plus there may be other safeguards?

Neither Tesla EVSE's or Quick Charge Power cables are approved. Never the less they work fine.

Current Tesla EVSE's are reduced current from the earlier ones. In my opinion pushing the P& B relay to 40A was bad. It is rated for non switching current of 4oA but it leaves no reserve.