Wire gauge (AWG) for HPWC (Telsa Wall Connector)

[jebinc]

Hello all,

I believe 6 gauge, stranded, is all one needs for a 60 amp circuit with 48 amps continues draw (HPWC) - for distances less than a certain amount of feet. My installation will be 35 running feet of wire from my main panel and I was thinking of going with 4 gauge wire (actually 4/3 cable) instead of the 6 gauge equivalent. I'm curious to know what you (or your electrician) used for your installation. Please state # of feet and whether you or your electrician did the install! Happy 48 Amps to you all!

 

[P85_DA]

I did install I used #3 THHN (#8 for ground) 100a breaker .. less than 5foot run..ur fine with #6

 

[dk10438]

100 A circuit, 2 Gauge wiring, 5 foot from breaker box

 

[jebinc]

100 A circuit, 2 Gauge wiring, 5 foot from breaker box

Why a 100 amp circuit? I thought the HPWC is limited to 48 amps of charging (80% of 60 amps)? Same question for @P85_DA

 

[dk10438]

Why a 100 amp circuit? I thought the HPWC is limited to 48 amps of charging (80% of 60 amps)?

no, 100 A circuit with 80A output is max. I charge at 72A which is the max for my car.

 

[jebinc]

no, 100 A circuit with 80A output is max. I charge at 72A which is the max for my car.

Hmmm, I wonder if I'm incorrect that my new M3 is limited to a 60 amp circuit / 48 amp draw... Anyone know for sure? I would love to bump it up to 80-100 amps. My HPWC is a Gen 2, if that makes a difference.

EDIT: Ah, max per car is 48 amps, for sharing, you can wire for multiple Tesla's. Guess I'll go with the 4 gauge wire - future proofing...

 

[P85_DA]

You are limited to 48a on M3 ..in my case early S had dual charger to get max 80a (why I did 100a) ..now on X I can only go up to 72a

Only reason to bump to 100a is if you want to load share on future with another WC the gen 2 can load share up to 3 WCs

 

[davewill]

Hmmm, I wonder if I'm incorrect that my new M3 is limited to a 60 amp circuit / 48 amp draw... Anyone know for sure? I would love to bump it up to 80-100 amps. My HPWC is a Gen 2, if that makes a difference.

You're not. In the past, there have been Teslas that could do 72a and 80a charging, but the highest current models can do is 48a.

 

[jebinc]

You're not. In the past, there have been Teslas that could do 72a and 80a charging, but the highest current models can do is 48a.

What gauge and amperage did you go with?

 

[Joey_82]

6 gauge should be good.

3 years ago I wired an EVSE for my non-Tesla EV. Needed 8 gauge for a 40A circuit (32A EVSE) but over-spec’d the wire to 6 gauge to future proof it for possible Tesla Wall Connector in the future.

In another house (my friend was building) we had the electrician run 2 gauge to the garage for a 100A subpanel to really future proof for multiple Wall Connectors (if needed one day).

 

[ZOMGVTEK]

The charger is inside the car, that's what limits the max charge power. The wall connector is just an extension cord to provide safe power to the internal charger. For a 60A circuit NEC says you'd need #6 copper. Most of the time #4 THHN is barely more than #6, and its not really any harder to run. So it gives you a smidge more margin for a buck. Unless you have very low electrical demand otherwise, I wouldn't run a pair of wall connectors on anything but a 60A breaker anyways. If you only have 100A service, 48A consumption is about the highest load you'd want to put on it anyways. In some homes that will be enough to overload the mains with A/C running.

 

[KJD]

Ampacity Charts - Cerrowire

6 gauge THHN in conduit is working well for me. You are correct in that the most the car (new model 3) will pull is 48 amps.

 

[davewill]

My M3 SR charges at 30a on a 40a circuit using 8ga NM cable (Romex) wire. Since the SR only does 32a max charging, it's all that's needed. It's the third generation of EV (LEAF, Rav4EV, Model 3) to charge on that circuit and EVSE.



I just installed a shiny new 14-50 on a 50a circuit. It uses 6ga THHN wire in conduit and could be upgraded to 60a with just a breaker change (and removing the outlet). It charges my Rav4EV at 40a.



BTW, the answer to your question in the OP is that 6ga wire is fine for a 60a circuit if it's individual wires in conduit, but if you use NM cable (Romex) then it requires 4ga.

 

[jebinc]

My M3 SR charges at 30a on a 40a circuit using 8ga Romex wire. Since the SR only does 32a max charging, It's all that's needed. It's the third generation of EV (LEAF, Rav4EV, Model 3) to charge on that circuit and EVSE.

View attachment 426693

I just installed a shiny new 14-50 on a 50a circuit. It uses 6ga THHN wire in conduit and could be upgraded to 60a with just a breaker change (and removing the outlet). It charges my Rav4EV at 40a.

View attachment 426699

BTW, the answer to your question in the OP is that 6ga wire is fine for a 60a circuit if it's individual wires in conduit, but if you use NM cable (Romex) then it requires 4ga.

Thanks! I'm going with 4 AWG stranded cable (4/3).

 

[Mrcarcrazy]

#3 THHN and 8 gauge ground. 60amp breaker. 2ft run to breaker box.

Reason for #3 was local availability constraints. Overkill beat the other options.

 

[Rockster]

100 A circuit, 2 Gauge wiring, 6 foot from breaker box. Two wall chargers sharing the same circuit. Charging an S with dual chargers at up to 80 amps and a LR 3 at up to 48 amps.

 

[jebinc]

I decided to pull the trigger on 4/3 Romex for my HPWC install. I ran the cable and am now just awaiting arrival of the HPWC on Tuesday (7/9). What did you all use?

 

[1.21GW]

4/3 Romex here

 

[brkaus]

6/3 Romex for me, but I’m on a 50a breaker.

 

[Kleenerth3]

Thanks! I'm going with 4 AWG stranded cable (4/3).

Good choice. My electrician suggested the same. When we get our 2nd Tesla, upgrade for 2 connectors is easy.
Switch out the 60 amp breaker for a 90 and chain the 2 HPWC'S on that circuit. I can't wait to upgrade!!!