Gen 3 Tesla and Gen 3 J1772 Wall Connector Install Write up with Photos!

[ReversePolarity]

I've got a Tesla Model Y charging using the mobile connector at 32 amps + NEMA 14-50 and a Jeep Wrangler charging using a standard 120V outlet which used to require 12+ hours to fully charge. Felt that it is time to do a much needed upgrade. Originally the electrician quoted $3000 for the parts and labor to run it across the garage... I thought that was too much so decided to do it myself with the help of a family member. Note... I'm not a licensed electrician, this stuff can really hurt you if you don't know what you're doing.

Gen 3 wall connectors... 1 with Tesla plug and 1 with J1772 plug

This was configured as a 40A circuit off a 50A breaker. A new circuit was run using ~30' of 1/2" EMT conduit and 8 AWG cable from home depot from a new subpanel that the solar company installed in my garage. Some wiring from the solar circuit had to be modified to accommodate (new ground bar was added, not pictured). Also bought a conduit bender to do a few 90 degree bends.

Conduit and wire was run above the cars in the 2-car garage into the other side of the garage. Template from the wall connector was used to drill the mounting holes

Base plate mounted and the wires secured. This was 2x 8AWG hot cables (120v each) and a 10awg ground cable (green).

Lastly push the main body of the wall connector on secure the 4 screws and we're finished!

Jeep is happily charging using Tesla Wall connector I was also surprised that the quality of Tesla's J1772 connector is much, much better than even public charging stations and most of the J1772 connectors out there. Its very well made. This J1772 Wall connector can also charge your Tesla... if you use the J1772 to Tesla adapter that came with the car. I did just that, to test the current and charging speed lol.

Task # 2 : Replace NEMA 14-50 plug with Gen 3 wall connector (i always charged my MY using a wall connector at 32A)

NEMA 14-50 uses 2 hot, 1 neutral and 1 ground and since the Wall connector uses 2 hot and 1 ground, one of the wires wasn't needed.

I found that the electrician used a punch out located low in the existing panel, and my OCD self wanted the wall connector higher up the wall. Luckily, the Wall connector is to be installed in my garage right behind the breaker box so i just had to find a relatively safe place to punch a new hole, so i picked this spot about 12" higher (feel free to let me know if i completely chose the wrong spot).

A hole was drilled in my panel using a step drill

Also drilled a hole thru the drywall in my garage.

To be continued

 

[ReversePolarity]

After holes are drilled the wire that was originally used to run to the NEMA 14-50 socket was re-run thru the new hole I drilled (this wire had a romex sleeve which protects the wire in between the breaker panel and the wall connector). 3 wires total - 2 hot and 1 ground.

I also didn't need to touch the original breaker, since the last electrician already had a 50A for the NEMA 14-50.

How it looks on the other side. This is a "rear entry" meaning no wires above or below the wall connector!

All wired up! Note that Tesla instruction dictate 2 mounts for stud mount, but after doing that. I thought it was still a bit flimsy.. i'd do 3 mounting points next time.

Main body installed and secured! The lower hole was where the NEMA 14-50 outlet used to be, the hole just below the wall connector was a "oops" hole.. pro tip: measure twice, drill once.

Wifi Setup... Firmware upgrade, input Amps set, and since I have 2 wall connectors in my garage, I used the Power Sharing function. The two wall connectors are on two separate 50A circuits and communicate by Wifi. I set "Max Total Draw" to 60A between the two.

Last but not least, the finer details. Drywall repair/patch below, not pictured is the texture + primer + paint.

 

[qdeathstar]

With 8 romex your maximum output should be set at 32 amps.

If your meterbase/panel is outsize incoming wires need to be below the main breaker.

 

[EVer Hopeful]

Two questions:

When you say "A new circuit was run using ~30' of 1/2" EMT conduit and 8 AWG cable from home depot from a new subpanel that the solar company installed in my garage. Some wiring from the solar circuit had to be modified to accommodate (new ground bar was added, not pictured)"; did you put the ground bar in the subpanel? ...because I thought subpanels didn't have a grounding bar, couldn't in fact have one


Did you link these two wall connectors at all? I'll have to read up on that again, but my understanding is that they can talk to each other and "agree" on how charging should be distributed. Maybe this is if they're on the same circuit to avoid overloading that branch


Also, where is that meter mounted?

 

[MacO512]

Two questions:

When you say "A new circuit was run using ~30' of 1/2" EMT conduit and 8 AWG cable from home depot from a new subpanel that the solar company installed in my garage. Some wiring from the solar circuit had to be modified to accommodate (new ground bar was added, not pictured)"; did you put the ground bar in the subpanel? ...because I thought subpanels didn't have a grounding bar, couldn't in fact have one

Subpanels should have a grounding bar, to isolate grounds from neutrals, and the bonding screw removed.

A main panel doesn't require a grounding bar, as both grounds and neutrals can be on the neutral bar, with the bonding screw installed.

Although its fine to have a grounding bar on a main panel for a cleaner install or if the panel may be converted to a sub later. Just when its the main the bonding screw should be installed.

Only time grounds and neutrals would not be separated in a sub panel is on an old install that is not up to current code as it doesn't have 4 conductors between main and sub panel.

 

[MacO512]

With 8 romex your maximum output should be set at 32 amps.

If your meterbase/panel is outsize incoming wires need to be below the main breaker.

Yes 8 guage romex can only have a 40 amp breaker which means the WC should send 32 amps. If the 8 guage romex was reused where is the neutral? If it was removed that might be a violation of the wire UL listing of the romex and fail code.

I'd assume the new black wire are THHN and thus fine for a 50 gauge circuit. I'd have personally done 6 gauge so you have full 60 amps available, but that also would require 3/4" EMT.... so really 50amps is totally fine.

 

[MacO512]

Overall I like the quality you did with the install, pictures, and agree $3k seems way overpriced, however......

Are you getting this permitted or inspected? Downside is this appears to possibly have some code violations, if not permitted could cause major insurance claim issue, red flag if selling the house, not utilize EV charger tax credits, so might be reasons others should not try and follow this example.

 

[Rocky_H]

I have a couple of questions about your amp ratings that are confusing to me.

This was configured as a 40A circuit off a 50A breaker.

The breaker usually defines the amp rating of the circuit. So it sounds like you are saying this both ways with two opposite numbers, that it's BOTH a 40 and a 50 amp circuit. Which is it?

The two wall connectors are on two separate 50A circuits and communicate by Wifi. I set "Max Total Draw" to 60A between the two.

That's not right. You can't have them set for 60A max total when neither of them is wired for that level. If they are each wired as 50A, then you need to set 50A as the max for either/or/both being shared that way.

And just a question: What was the wire gauge of the Romex in that 14-50 outlet? If it was 8 gauge, then that can't be used as a 50A circuit. That one would need to be as a 40A. If it was 6 gauge though, then yes, a 50A circuit would be OK there. The 8 gauge individual wires in conduit is properly rated for a 50A circuit though on the other one.

 

[MacO512]

I have a couple of questions about your amp ratings that are confusing to me.


The breaker usually defines the amp rating of the circuit. So it sounds like you are saying this both ways with two opposite numbers, that it's BOTH a 40 and a 50 amp circuit. Which is it?


That's not right. You can't have them set for 60A max total when neither of them is wired for that level. If they are each wired as 50A, then you need to set 50A as the max for either/or/both being shared that way.

And just a question: What was the wire gauge of the Romex in that 14-50 outlet? If it was 8 gauge, then that can't be used as a 50A circuit. That one would need to be as a 40A. If it was 6 gauge though, then yes, a 50A circuit would be OK there. The 8 gauge individual wires in conduit is properly rated for a 50A circuit though on the other one.

Agree that first comment is unclear; if he means the subpanel has a 50 amp main breaker then a 40 amp breaker on the EV circuit is fine. If he has a 50 amp breaker on a 40 amp circuit as you say no that is not ok.

I'm not sure how the Tesla power sharing exactly works; if you can set the correct breaker limit for each WC individually, then separately configure total power sharing draw to be 60 amp combined perhaps that is fine and how the setup is intended? I'd assume in that case each individual WC still won't exceed their breaker limit such as 40 amps.

 

[Rocky_H]

I'm not sure how the Tesla power sharing exactly works; if you can set the correct breaker limit for each WC individually, then separately configure total power sharing draw to be 60 amp combined perhaps that is fine and how the setup is intended? I'd assume in that case each individual WC still won't exceed their breaker limit such as 40 amps.

It's kind of both. It's individually and as a group. I am rethinking this, and I think I am incorrect on my previous statement. 60A total may be fine. Since they are both wired into the main panel, you don't have the feed into the subpanel as a separate line limiting amp level. I was thinking 50A feeder, and then split to 50A to each wall connector. In that case, nothing could allow 60A. But in this case, since each one does get configured in the software for 50A circuits, neither should run over 40A per each one, and if you want to allow up to 60A total from the main, then I guess that is fine.

 

[ReversePolarity]

With 8 romex your maximum output should be set at 32 amps.

If your meterbase/panel is outsize incoming wires need to be below the main breaker.

Thanks for pointing it out; I couldn't edit the post anymore but the EMT has 8 awg and the second charger (NEMA14-15 converted to Wall Charger) is a 6 awg romex (with all but 3" of sleeve stripped out).

 

[ReversePolarity]

did you put the ground bar in the subpanel? ...because I thought subpanels didn't have a grounding bar, couldn't in fact have one


Did you link these two wall connectors at all? I'll have to read up on that again, but my understanding is that they can talk to each other and "agree" on how charging should be distributed. Maybe this is if they're on the same circuit to avoid overloading that branch


Also, where is that meter mounted?

We added a ground bar inside the subpanel (photo shots before adding).

The two wall connectors are linked and talk to each other via Wifi. They are on different charging circuits (40a with 50a breaker)

I'd assume the new black wire are THHN and thus fine for a 50 gauge circuit. I'd have personally done 6 gauge so you have full 60 amps available, but that also would require 3/4" EMT.... so really 50amps is totally fine.

The wire thru the new 1/2" EMT (conduit) is 8awg THHN. I thought about 60 amp briefly but thought 50 was the best bang for the buck (and time).

Are you getting this permitted or inspected? Downside is this appears to possibly have some code violations, if not permitted could cause major insurance claim issue, red flag if selling the house, not utilize EV charger tax credits, so might be reasons others should not try and follow this example.

When the panels were opened up there were several issues not up to code, and this was right after the city signed off on it including wrong breakers, incorrect wiring method. It probably wouldn't have burned the house down but they were rectified.

That's not right. You can't have them set for 60A max total when neither of them is wired for that level. If they are each wired as 50A, then you need to set 50A as the max for either/or/both being shared that way.

And just a question: What was the wire gauge of the Romex in that 14-50 outlet? If it was 8 gauge, then that can't be used as a 50A circuit. That one would need to be as a 40A. If it was 6 gauge though, then yes, a 50A circuit would be OK there. The 8 gauge individual wires in conduit is properly rated for a 50A circuit though on the other one.

There were two settings available inside the wall connector setup - max current for each wall connector (set to 40A) and max total current during the power share (set to 60A). Hypothetically under this setting each wall connector wouldn't go above 40A and when they are both in use, the total combined wouldnt exceed 60A, meaning one could be at 40A and other could be 20A. Although i havent tested this just yet.

The wire gauge in the 14-50 outlet is 6awg. This outlet was run by a real electrician and looks like they done it right. I just modified and ran the existing wire into a wall charger. thanks for checking.

 

[ReversePolarity]

Agree that first comment is unclear; if he means the subpanel has a 50 amp main breaker then a 40 amp breaker on the EV circuit is fine. If he has a 50 amp breaker on a 40 amp circuit as you say no that is not ok.

I'm not sure how the Tesla power sharing exactly works; if you can set the correct breaker limit for each WC individually, then separately configure total power sharing draw to be 60 amp combined perhaps that is fine and how the setup is intended? I'd assume in that case each individual WC still won't exceed their breaker limit such as 40 amps.

It's kind of both. It's individually and as a group. I am rethinking this, and I think I am incorrect on my previous statement. 60A total may be fine. Since they are both wired into the main panel, you don't have the feed into the subpanel as a separate line limiting amp level. I was thinking 50A feeder, and then split to 50A to each wall connector. In that case, nothing could allow 60A. But in this case, since each one does get configured in the software for 50A circuits, neither should run over 40A per each one, and if you want to allow up to 60A total from the main, then I guess that is fine.

My first post lacked some details and combined with "non standard" wording it created some confusion. The chargers are in fact on two different circuits, one charger is connected directly to the main panel (50A breaker, 6awg romex) and second charger is connected to the subpanel (50a breaker, 8awg thhn). But yeah, a 50A feeder into two 50A breakers would have been silly

Software is configured to 40A max (each individual charger) -and- 60A max (all chargers combined).

 

[Rocky_H]

But yeah, a 50A feeder into two 50A breakers would have been silly

Well, no, it wouldn't have been silly. That's how it's commonly done, and is exactly the purpose of the communication sharing function. You can have one 50A main feeder line to a subpanel, and then you can hang 3 or 4 or 5 50A circuits on there, and as long as they are set for sharing to not exceed the 50A circuit parent line, they all manage themselves well. Cars will charge, and as one finishes, it can shift a bit more current to others.

 

[ReversePolarity]

Gotcha. Mine came out of separate panels so didn't check if they can be wired up in a strings, that sounds fairly convenient as long as the total power available is sufficient.

 

[TunaBug]

Thanks for your illustrations and sharing your experience!

It looks like in your 3rd and 4th pictures you are using the same black wire for the two different hot legs. Should have been black and red, at this point I think you can fix it by adding red tape to both ends of one of them. Be sure the red tape is at both ends of the same wire, not different ends of different wires

 

[MacO512]

Gotcha. Mine came out of separate panels so didn't check if they can be wired up in a strings, that sounds fairly convenient as long as the total power available is sufficient.

They can't be on a shared wire to one breaker. They each need a dedicated wire straight to their own breaker. But they can be on a sub panel with multiple breakers that feed into a single "parent" breaker.

 

[davewill]

Thanks for your illustrations and sharing your experience!

It looks like in your 3rd and 4th pictures you are using the same black wire for the two different hot legs. Should have been black and red, at this point I think you can fix it by adding red tape to both ends of one of them. Be sure the red tape is at both ends of the same wire, not different ends of different wires

I don't believe this is actually required. He should be able to leave the two hots black.

 

[Mrbrock]

What is the point of power sharing if they are on separate panels? Who told you that 60A is your max total draw? If there is a limit on the sub panel then a breaker smaller than 50A should be used.

Also, does the breaker for the J1772 in the solar panel share the same wiring back to the main panel as your solar breakers? That doesn’t sound right, like there could be some situation where that wire ampacity is overdrawn.

 

[Rocky_H]

Thanks for your illustrations and sharing your experience!

It looks like in your 3rd and 4th pictures you are using the same black wire for the two different hot legs. Should have been black and red, at this point I think you can fix it by adding red tape to both ends of one of them. Be sure the red tape is at both ends of the same wire, not different ends of different wires

I don't believe this is actually required. He should be able to leave the two hots black.

I was really curious on this. I sure thought you would have to mark one of the wires to distinguish it, but I did some searching. It looks like you don't have to.

Can I use 2 black THHN wires for a 240v line?

I'm going to be wiring a 50A 240V circuit to a shed through an MF conduit. There will be about 3 feet of conduit connecting to a subpanel and it will remain above ground. I know the neutral wire mu...

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