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How much did your HPWC installation cost?

I am being quoted prices between $830-960CAD+tax for what I think is a relatively simple installation. I only need 20'-25' of cables, the electrical panel is in the back of the garage and I want to place the wall connector at the front of the garage on the exterior wall.

Also, am I being charged a Tesla tax? When I asked one of the electricians for a quote, he told me it would be $660 (30A breaker, 6 gauge cable). I told him I needed 60A for a Tesla and now he quoted me $830 which is $170 more. At home depot the 60A breaker is only $20 more and the difference between 4AWG and 6AWG cables is around $2-3 per meter so the extra materials should only be $40.
 

Rocky_H

Well-Known Member
Feb 19, 2015
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Boise, ID
This is entirely dependent on the state you live in. NEC 2020 code says yes, an outlet requires a GFCI breaker,
but many states are still using 2017
...which stated that outlets being installed for the purpose of EV charging required a GFCI breaker, so it was added in the 2017 version. Why they think that the intended purpose makes a difference seems entirely stupid to me. And @RayK mentioned:
A secondary use of the 14-50 would be to power my daughter's RV when she visits
Sooo, depending on what the "intended" use of it is, it might or might not require it, which is a dumb way to write electric code.
or even 2014 code (like Virginia).
OK, yes, the 2014 version of code didn't require the GFCI breakers on these at all.
 
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...which stated that outlets being installed for the purpose of EV charging required a GFCI breaker, so it was added in the 2017 version. Why they think that the intended purpose makes a difference seems entirely stupid to me.

This is true for the states that adopted NEC 2017 and 2020 (and I agree with you, it's stupid) - but I don't believe that requirement is applicable to those that have/want a HPWC; it only impacts those that run a 14-50 outlet.
 
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Rocky_H

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Feb 19, 2015
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Boise, ID
what is the benefit of GFCI on a NEMA 14-50?
The so-called "benefit" is just legally complying with a requirement in the National Electric Code.
Pretty sure my hot tub doesn't have one and that's me submerged in water.
Hot tubs ABSOLUTELY DO require GFCI circuits. Your not having one is between you and your conscience.
 
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GFCI's are required on 14-50's for many reasons:
- It's easily possible to touch the conductors during insertion/removal
- It's possible for other things to touch the conductors of a partially inserted plug (e.g. a rake or yardstick leaning against the same wall)
- It's possible for the consumer product cord to become damaged in a way that exposes conductors
- Much of the rationale for requiring protection on all the other outlets (120V) also applies to 240V outlets

I suspect the special rule for EV outlets came about because the NFPA wanted to react quickly to the sudden increase in 240V outlet installations in very accessible locations (not behind a dryer or oven) but also wanted to give the industry (tablesaw, welder, etc.) some time to adapt as needed.
 
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Randy Spencer

Supercharger Hunter
Mar 31, 2016
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Alameda, CA
GFCI's are required on 14-50's for many reasons:
- It's easily possible to touch the conductors during insertion/removal
- It's possible for other things to touch the conductors of a partially inserted plug (e.g. a rake or yardstick leaning against the same wall)
I think those are situations that would blow the breaker, GFCI works by seeing more power going in than coming out of a circuit, so they put them in areas where water could create a path for electricity to ground, so Kitchens, baths, and garages.

I supposed my hot tub may have a GFCI at the tub itself, but there isn't a GFCI in my breaker panel for the tub, or for my RVs 14-50 that I use to charge the Tesla with it's UMC. I guess you could get a GFCI breaker and replace the on that's currently in the panel for the 14-50, I just don't get the point. No sink near the outlet, not exposed to the weather
 
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BillRadio

Member with an Altitude
Jan 2, 2022
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Denver
I am being quoted prices between $830-960CAD+tax for what I think is a relatively simple installation.
Your quotes sound reasonable. I got 3 quotes just to add the charging circuit that were well over $1,000 USD. I Did need some breaker consolidation.

Do you you really need a 60A breaker? That is just a bit beyond the limit of 6/3 wire. You would be safer with 50A and would still charge within a few hours each night.

Would you save by putting the WC closer to the breaker panel? Not as much as you'd hope. This is not the time to pinch pennies. Do it right today and you'll appreciate your wisdom a year from now.
 
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Your quotes sound reasonable. I got 3 quotes just to add the charging circuit that were well over $1,000 USD. I Did need some breaker consolidation.

Do you you really need a 60A breaker? That is just a bit beyond the limit of 6/3 wire. You would be safer with 50A and would still charge within a few hours each night.

Would you save by putting the WC closer to the breaker panel? Not as much as you'd hope. This is not the time to pinch pennies. Do it right today and you'll appreciate your wisdom a year from now.
I got another quote from someone else for $800CAD. They will completely hide the cable through the ceiling and the wall and they will use 6/2 cable. I’ll ask them to use 6/3 since it’s just $5/m extra and would allow me to fit a NEMA 14-50 in the future. Theyre using 90C cable so even if it’s 6AWG, it can go up to 75A.

Since I have the SR+ that only charges at 40A, there would be no difference between 60A or 50A but I prefer having a good installation and not needing to upgrade in the future.
 
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Sophias_dad

Active Member
Supporting Member
Jul 29, 2018
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Massachusetts
I got another quote from someone else for $800CAD. They will completely hide the cable through the ceiling and the wall and they will use 6/2 cable. I’ll ask them to use 6/3 since it’s just $5/m extra and would allow me to fit a NEMA 14-50 in the future. Theyre using 90C cable so even if it’s 6AWG, it can go up to 75A.

Since I have the SR+ that only charges at 40A, there would be no difference between 60A or 50A but I prefer having a good installation and not needing to upgrade in the future.

The SR+ only charges at 32 amps(80% of 40).


At least in the US, that NM-B cable through the ceiling(or anywhere) is >required< to use the 60C rating. Additionally, even if the wire itself is allowed to use the 90C rating, the HPWC's terminals are only rated for 75C. That 75C is good enough to move 65 amps through #6.


In real-world-usage, I wouldn't worry that much about sending 48 amps continuous though #6 even if we assume the 60C rating. The 60C rating is good for 55 amps, and 80% of that is 44 amps is not that much less than 48. Assuming quebec doesn't have a heat wave, you can probably use ambient air temperature adjustments to add a couple percent to that 44 rating.
 
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The SR+ only charges at 32 amps(80% of 40).


At least in the US, that NM-B cable through the ceiling(or anywhere) is >required< to use the 60C rating. Additionally, even if the wire itself is allowed to use the 90C rating, the HPWC's terminals are only rated for 75C. That 75C is good enough to move 65 amps through #6.
This is the cable that they want to use. It says NMD, is that different than NM-B? Also, this is the cable that I’m going to ask them to use instead. Would it be good for a NEMA 14-50.

Their quote says that everything they will do respects Quebec’s electrical code so I’m assuming that if they do something that isn’t allowed, I can just tell them to fix it.
 
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Sophias_dad

Active Member
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Jul 29, 2018
2,188
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Massachusetts
This is the cable that they want to use. It says NMD, is that different than NM-B? Also, this is the cable that I’m going to ask them to use instead. Would it be good for a NEMA 14-50.

Their quote says that everything they will do respects Quebec’s electrical code so I’m assuming that if they do something that isn’t allowed, I can just tell them to fix it.
Looks like your plan is fine. NMD is a Canada thing apparently, and yes, the 6-3 would be fine for an eventual 14-50.
 
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