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What NEMA plug/outlet wiring is closest to HPWC (for later upgrade?)

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So, I have my solar installers coming out in precisely 7 days. I'm paying them to install the HPWC for my 3 while they're here.

Agreement is for a 60 amp circuit so I'll get 48a to the 3 through the HPWC.

Waiting on a Signature Edition HPWC. No sign of it.

In the meantime, ordered a standard grey HPWC, today. Not sure if it will show up on time.

So, my question is this-- In the event that I have no HPWC on installation day, what outlet should I have the solar installers put in place that will have the closest wiring/box/etc to what the HPWC needs? I'm thinking in terms of ground/neutral/poles for 240v/60a service. I know the NEMA 15-50 is a 50 amp circuit. I'm sure I can talk them into using adequate wire gauge to support 60a on that outlet, and later 'upgrade' it myself. I've seen the HPWC installation video and the wiring is dead simple. I'm totally capable of killing the breaker, yanking an outlet, and installing the HPWC. But I'm no electrician, so I can only do this if the wiring provided to the outlet closely mimics what I'll need for the HPWC. And of course there's the matter of whether they pull the wires from the wall (behind the charger/outlet) vs via conduit. But all of those things I can deal with; if they use conduit, i'll use that conduit for my HPWC. If they do it behind the wall, I'll mount my HPWC over the top.

So, what say you? Which outlet will be wired up with exactly the wires I need for a HPWC? Maybe this is a stupid question, but I'm currently using a 10-30 (via extension cord, from a totally different location), and I've been scared by talk of ungrounded outlets and the like, so I want to make sure, if I'm paying someone for wiring, it looks like what I'll need to hook up the HPWC later. Hell, even if I end up paying an electrician to swap an outlet for the HPWC later, it makes sense to have the 'right' circuit.

thanks in advance!
 
14-50 ....

Well, good to hear; that helps, since we've all got 14-50 adapters for the mobile charger anyway :)

Outlets (even weatherproof ones) are cheap, no reason I can't get wiring adequate for 60a to the 14-50, use the mobile charger in the meantime. As much as I want a permanently solution, hell, if the grey HPWC doesn't ship soon, I might just cancel it and wait 1/2/3/4/5/6 months for the signature one.

Thanks for the quick reply!!
 
So, I have my solar installers coming out in precisely 7 days. I'm paying them to install the HPWC for my 3 while they're here.

Agreement is for a 60 amp circuit so I'll get 48a to the 3 through the HPWC.

Waiting on a Signature Edition HPWC. No sign of it.

In the meantime, ordered a standard grey HPWC, today. Not sure if it will show up on time.

So, my question is this-- In the event that I have no HPWC on installation day, what outlet should I have the solar installers put in place that will have the closest wiring/box/etc to what the HPWC needs? I'm thinking in terms of ground/neutral/poles for 240v/60a service. I know the NEMA 15-50 is a 50 amp circuit. I'm sure I can talk them into using adequate wire gauge to support 60a on that outlet, and later 'upgrade' it myself. I've seen the HPWC installation video and the wiring is dead simple. I'm totally capable of killing the breaker, yanking an outlet, and installing the HPWC. But I'm no electrician, so I can only do this if the wiring provided to the outlet closely mimics what I'll need for the HPWC. And of course there's the matter of whether they pull the wires from the wall (behind the charger/outlet) vs via conduit. But all of those things I can deal with; if they use conduit, i'll use that conduit for my HPWC. If they do it behind the wall, I'll mount my HPWC over the top.

So, what say you? Which outlet will be wired up with exactly the wires I need for a HPWC? Maybe this is a stupid question, but I'm currently using a 10-30 (via extension cord, from a totally different location), and I've been scared by talk of ungrounded outlets and the like, so I want to make sure, if I'm paying someone for wiring, it looks like what I'll need to hook up the HPWC later. Hell, even if I end up paying an electrician to swap an outlet for the HPWC later, it makes sense to have the 'right' circuit.

thanks in advance!

If you spec'd at least 60a capable (48a continuous) to the HPWC they will either do 6 awg copper in conduit, OR 4 awg copper in NM (romex) cable. Most likely 6 awg in conduit would be my guess.

So as @P85_DA points out, to temporarily wire it to a NEMA 14-50 receptacle would require adding an *extra* conductor for the neutral which they may not want to do since it is extra useless copper burned and it might require larger conduit to fit it. Note that you would also need to spend $10 to get a 50a breaker which would later be swapped to the 60a breaker when the HPWC is installed. Really, the right receptacle for this is a 6-50 instead of the 14-50. The 6-50 is still 50a rated, but just minus the neutral conductor. But you would need a UMC Gen 2 adapter for the 6-50 (costs $35).

P.S. I actually installed a 14-50 AND a HPWC just so I had options. The HPWC is outside and the 14-50 is in the garage right under the panel. This provides me maximum flexibility.
 
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If you spec'd at least 60a capable (48a continuous) to the HPWC they will either do 6 awg copper in conduit, OR 4 awg copper in NM (romex) cable. Most likely 6 awg in conduit would be my guess.

So as @P85_DA points out, to temporarily wire it to a NEMA 14-50 receptacle would require adding an *extra* conductor for the neutral which they may not want to do since it is extra useless copper burned and it might require larger conduit to fit it. Note that you would also need to spend $10 to get a 50a breaker which would later be swapped to the 60a breaker when the HPWC is installed. Really, the right receptacle for this is a 6-50 instead of the 14-50. The 6-50 is still 50a rated, but just minus the neutral conductor. But you would need a UMC Gen 2 adapter for the 6-50 (costs $35).

To clarify: The 14-50 is the one that requires the neutral, where the HPWC does not? Since you say the 6-50 is the same, minus a neutral, and same wiring for the HPWC? I could go either route; I don't mind ordering a 6-50 adapter, hell I bought a 10-30 that I'll only have used a few times by the time this all gets installed!

My HPWC/outlet/whatever will go within a foot or two of the panel on the outside of the house, so wiring run length is not a particular issue. Hopefully I'll know within a day or two whether the HPWC will ship in time.
 
To clarify: The 14-50 is the one that requires the neutral, where the HPWC does not? Since you say the 6-50 is the same, minus a neutral, and same wiring for the HPWC? I could go either route; I don't mind ordering a 6-50 adapter, hell I bought a 10-30 that I'll only have used a few times by the time this all gets installed!

My HPWC/outlet/whatever will go within a foot or two of the panel on the outside of the house, so wiring run length is not a particular issue. Hopefully I'll know within a day or two whether the HPWC will ship in time.

Yeah, 6-50 is basically the same as a 14-50 just it has one less pin (the neutral). The UMC does not need the neutral and the HPWC does not even have a place to land a neutral conductor since it does not use it.

Usually 14-50 receptacles can handle up to 4 AWG wire I think, and I doubt your electricians are planning on any thicker gauge than that if you only spec'd 60a needed for the HPWC.

Note that mounting wise: The HPWC is a hanger in itself for the cable. So I would make sure it is mounted at an appropriate height to use in that fashion. For permanent installs, I would generally put a 14-50 or 6-50 outlet low down on the wall so that I don't burn a lot of cable length getting from the outlet to the floor (though maybe you don't need the cable length anyway). But clearly you are going to optimize for the final HPWC mounting location in whatever you do temporarily...
 
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Note that mounting wise: The HPWC is a hanger in itself for the cable. So I would make sure it is mounted at an appropriate height to use in that fashion. For permanent installs, I would generally put a 14-50 or 6-50 outlet low down on the wall so that I don't burn a lot of cable length getting from the outlet to the floor (though maybe you don't need the cable length anyway). But clearly you are going to optimize for the final HPWC mounting location in whatever you do temporarily...

One note of caution, based on experience: if you are using the HPWC inside a garage with painted drywall, the cable may leave black scuff marks if wrapped in this fashion. I found that mounting the HPWC a little higher and using a cable hanger to be better aesthetically. :D
 
If you don't want to ask to have wiring installed for an EV for fear of price hiking, just ask for a 100A welding circuit. Tell them you will install the outlet once you figure out what type you will need. You'll end up with both a neutral and a ground when you only need a ground, but that's OK. It's easy enough to not use a wire when connecting up the HPWC.
 
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This is all great advice. Thankfully, my HPWC shipped and will be here 2 *days* before the installation is scheduled. Totally self-inflicted stress, but I was hoping the Tesla Signature charger would ship so I wouldn't have to pay actual money for one. No signs of those actually existing in the wild yet, though.
 
So, if I install a HPWC and end up moving to a new place, could I replace it with a 6-50 outlet?
You could also just turn off the breaker, cap off the wires, and put a cover on the junction box. Personally, I wouldn't change the breaker and add the outlet unless I knew it was going to be used for something. The new tenant could want to install another HPWC and just have to undo what you've done. They might not even realize that the circuit could support a bigger breaker if you change it.
 
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If I could do it all over again I would have mounted the HPWC in the attic above my garage and dropped the charging cable down through a hole in he ceiling so that it would Hang 18 inches off the floor next to my charging port.
Garages are supposed to be sealed from the rest of the house, so you shouldn't have an unsealed hole in the ceiling. Besides, it would be a nuisance to not be able to see the lights on the EVSE if things weren't working right. No reason you couldn't mount it ON the ceiling if you really wanted to, or use a hook.
 
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My garage is close cell foamed and has a barrier between the living space and the garage, so complete isolation. My air compressor is already up there and so is a high pressure washer and vacuum.


I dont need to see the lights as i get a visual cue when i plug in plus a text message telling me charging has begun and when it completes. Also hate cluttering the garage with other crap that creates a tripping hazard.

3 Model S’s and over 150,000 Miles’s tells me i wish to god i. Had mounted this crap in the attic.


upload_2018-7-25_19-37-40.jpeg
 
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Garages are supposed to be sealed from the rest of the house, so you shouldn't have an unsealed hole in the ceiling. Besides, it would be a nuisance to not be able to see the lights on the EVSE if things weren't working right. No reason you couldn't mount it ON the ceiling if you really wanted to, or use a hook.
I did end up using hooks, but it’s ugly and adds clutter to my garage.