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Tesla wall charger users. What size wire is your charger using?

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If they had a wall connector that could be set for a 55a circuit (44a charging), then the 60a breaker would make some sense, but otherwise it's just lowering the protection of the circuit for no purpose. Not to mention the chance that some future owner might think that this was actually a 60a circuit based on the breaker and dial up the wall connector to 48a charging erroneously.

There will be no future owner in the distant future, and if we leave the HPWC is coming with us. The circuit is perfectly fine for a non continuous load for anything else in the garage. We used a 60amp because that’s what we bought before we realized 6/2 wasn’t rated enough to pull 48amps. Everything is NEC compliant so I’m not touching it.
 
There will be no future owner in the distant future, and if we leave the HPWC is coming with us. The circuit is perfectly fine for a non continuous load for anything else in the garage. We used a 60amp because that’s what we bought before we realized 6/2 wasn’t rated enough to pull 48amps. Everything is NEC compliant so I’m not touching it.
Nobody truly knows what the future may bring. Any one of us could be dead or incapacitated tomorrow. Plus even if you DO take the wall connector with you, you'd still be leaving that weird circuit behind that someone else could well mistake for a real 60a circuit and install their own wall connector on.

Anyway, I wasn't really trying to convince you, just pointing out that others shouldn't emulate you.
 
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If they had a wall connector that could be set for a 55a circuit (44a charging), then the 60a breaker would make some sense, but otherwise it's just lowering the protection of the circuit for no purpose. Not to mention the chance that some future owner might think that this was actually a 60a circuit based on the breaker and dial up the wall connector to 48a charging erroneously.


I hear you.... but, it’s code compliant.
 
Question - if I want to install a wall charger and be able to future proof it to maybe have a nema 14-50 and wall charger or two wall chargers later, what size breaker and wire should I use? And would it be okay to run a higher breaker if I am only using a single wall charger on the meantime?
 
Question - if I want to install a wall charger and be able to future proof it to maybe have a nema 14-50 and wall charger or two wall chargers later, what size breaker and wire should I use? And would it be okay to run a higher breaker if I am only using a single wall charger on the meantime?
Sure, you can set the single wall charger for whatever size circuit you would install for a power sharing arrangement. Now a 14-50 can't be on a breaker larger than 50a. If your only consideration is future-proofing, I'd be inclined to run a maximum sized circuit to a small subpanel or load center, then run my single wall connector and/or 14-50 off of that. When you add more wall connectors later, you do it, by adding their circuit to the subpanel, and configuring them to share the circuit feed to the subpanel.

Example 1. You run a 100a circuit to the subpanel. From the subpanel, run wire for a 100a circuit to your wall connector, use a 100a breaker and set the WC for 80a charging. When you add WC#2, run another 100a circuit and breaker from the subpanel, connect the two WCs with a data wire, and configure them to load share the 100a.

Example 2. Same 100a circuit to the subpanel. Run wire for a 100a circuit to the WC, but use a 60a breaker and configure the WC for 48a charging. Run a 50a circuit with 50a breaker from the subpanel to a 14-50 to use as a second or backup charging circuit. This should be OK since the max load is 48a from the WC and 32a from the UMC, which fits in the total 80a load available in the 100a feeder circuit. If the inspector doesn't like it, you can use a 40a breaker on the 14-50 and not lose any actual charging capacity. When WC#2 comes along, remove the 14-50 circuit breaker, up the breaker for WC#1 to 100a, run another 100a circuit from the subpanel for WC#2, connect the two with a data wire, and configure them to load share the 100a.

If 100a is too much and you want to use an 80a feeder instead, Example 1 stays the same except you use 80a wire and breakers.
 
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Sure, you can set the single wall charger for whatever size circuit you would install for a power sharing arrangement. Now a 14-50 can't be on a breaker larger than 50a. If your only consideration is future-proofing, I'd be inclined to run a maximum sized circuit to a small subpanel or load center, then run my single wall connector and/or 14-50 off of that. When you add more wall connectors later, you do it, by adding their circuit to the subpanel, and configuring them to share the circuit feed to the subpanel.

Example 1. You run a 100a circuit to the subpanel. From the subpanel, run wire for a 100a circuit to your wall connector, use a 100a breaker and set the WC for 80a charging. When you add WC#2, run another 100a circuit and breaker from the subpanel, connect the two WCs with a data wire, and configure them to load share the 100a.

Example 2. Same 100a circuit to the subpanel. Run wire for a 100a circuit to the WC, but use a 60a breaker and configure the WC for 48a charging. Run a 50a circuit with 50a breaker from the subpanel to a 14-50 to use as a second or backup charging circuit. This should be OK since the max load is 48a from the WC and 32a from the UMC, which fits in the total 80a load available in the 100a feeder circuit. If the inspector doesn't like it, you can use a 40a breaker on the 14-50 and not lose any actual charging capacity. When WC#2 comes along, remove the 14-50 circuit breaker, up the breaker for WC#1 to 100a, run another 100a circuit from the subpanel for WC#2, connect the two with a data wire, and configure them to load share the 100a.

If 100a is too much and you want to use an 80a feeder instead, Example 1 stays the same except you use 80a wire and breakers.

Thanks for the input Dave, what size wire should I be using?
 
Thanks for the input Dave, what size wire should I be using?

Use #2 or #3 THHN (#3 can be hard to find and is often no cheaper than #2) for the 100a circuits, #4 THHN for an 80a circuit, #6 THHN for a 60a circuit, #8 THHN or #6 Romex for a 50a circuit, and #8 THHN or Romex for a 40a circuit. You can use a bigger wire so long as the breaker and the device or outlet is able to accept that size. The 50a breaker and 14-50 outlet may not be able to accept larger than #4, for instance...but read the specs to find out for sure.

Use the left two columns in the following table for reference. The 60C column for Romex and the 75c column for THHN (individual wires in conduit). I know that THHN is listed in the 90C column, but the breakers and other items will only be good for 75C, so use that column.

View attachment 467339

screen-shot-2019-10-17-at-10-27-26-pm-png.467339
 
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Sorry if this is a dumb question but what is the difference between #6 THHN and 6/3 romex? Isn't the 6/3 Romex comprised of 6 awg THHN wire?
Mines 444 with a 6g ground. 60 amp was gunna be 6666. As long as you’re the gauge required for the amperage you’ll be good. The charts posted here or with a quick google search show the proper wire to use very clearly.

And talk to your guys at your local electric supply shop they will know for sure. Cost me 90ish bucks for 50 feet of the 4g. That was the 6g price as they were out, 4g is about 2x more. Save me 500 bucks for an electricians cost on “materials”
 
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Sorry if this is a dumb question but what is the difference between #6 THHN and 6/3 romex? Isn't the 6/3 Romex comprised of 6 awg THHN wire?
Yes, they are both No. 6 but:

The Romex is in a cable (Type NM-B) with insulation rated to 60 °C and the THHN is an individual wire rated to 90 °C when there are up to 3 current carrying ones in a conduit. Thus #6 Romex is good up to 55 amps whereas #6 THHN is good up to 75 amps but you must have a circuit breaker with terminals rated for 90 °C to run it that high. So most people use THHW or THWN which is 75 °C rated and can handle 65 A. Of course there is no reason you can't run #6 THHN at #6's 75 ° rating.
 
The chart above is based on an ampacity rating for a 100 ft run I believe? If you are trying to strictly meet code the chart provided is correct and you probably should charge at 40 amps.

I used #6 right in to the back of the charger, and mounted it flush to the wall on a stud at one side of the bracket and drywall anchors on the other. The romex is behind drywall and the total length is less than 18 inches direct to the 60 amp breaker. Technically that is probably out of code at five amps over, but safety wise it exceeds any required spec because of the short length of the run. If you check the ampacity rating of an 18 inch piece of number 6 you will get quite different results due to the overall decreased resistance of the wire. So depending on the distance from your breaker box to the charger you may or may not be able to safely charge at 48 amps using number 6.

I always get charge levels at 12+ kilowatts ranging from 240v at 48 amps and sometimes up to 247v resulting in a 47 amp draw.

Always be safe and use an electrician if you are not sure what you are doing.