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Adding a 2nd Tesla home charger and tapping the wires.

mongo

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Good points, not sure why my electrician did the 6/2 romex, I did question it but he said it was fine, also why my town approved it…..
If it was a feeding a 6-50 outlet, it would be fine.

So it reads like you still have the 6/2 romex from the panel to the subpanel? If so, the 60a breaker is not code compliant, and could fail to protect the romex in an overload situation.
60A breaker is code compliant under 240.4(B)

If you want to do it right run 6/2 MC from main panel to sub panel.
Where's the neutral?

It's always been written NOT to use Romex for wall connector wiring.
Where has this always been written?
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That Beast Mode

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So it reads like you still have the 6/2 romex from the panel to the subpanel? If so, the 60a breaker is not code compliant, and could fail to protect the romex in an overload situation. Is it "probably safe"? Sure, but that exceeds my risk tolerance, since a fire is the potential outcome.

You do you, but I would highly recommend throttling back to 40a, and replacing the 60a with a 50a breaker at both the panel and subpanel.

Or do like me, and have a proper run done right next to the incorrect one because my homebuilder didn't do what I asked lol.
If the Romex is on a 50A breaker at the panel it would still be protected, even if he has 60A at the sub panel but I think you would still be limited to 40A charging because that is your weakest link. I chose to go a step down, I have a 50A on the Romex, I'd rather have it under the rating than slightly over. I know a bunch of people have run it on a 60A and don't have issues, I wasn't willing to take that chance to charge a little bit faster. I charge it overnight anyway, so an extra hour or whatever doesn't matter to me.
 

JerseyMike

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Why 40A? My calculation is 44A is fine and that’s what I set PowerShare max to….55x.8=44A
 

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Where's the neutral?

Where has this always been written?
Neutral? None needed. This is only for Tesla Wall Connector, 2 hots and a ground. That's it. 6/2 MC.

Written? In just about every post I've read for the past 10 years about wiring for Tesla Wall Connectors.

This circuit follows the 80% rule. These are constant long use circuits.

Am I an electrician? No. I read a lot and validate what I read with detailed research.

Hope this helps. Don't take my word for it, do your own research. There is plenty of info out there. Your task is to separate the fact from the fiction.

PS: ELECTRICITY IS DANGEROUS. IF YOU DON'T KNOW WHAT YOUR DOING STEP ASIDE AND GET SOMEONE WHO DOES. LIVE FOR ANOTHER DAY.
 
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Where's the neutral?
When I was receiving bids for my condo association to have our parking garage wired for EVs, I checked a handful of chargers -- they were all L1/L2/GFI. Although the Ford did have neutral listed as "optional." I did end up talking the electrician who took our bid into wiring neutral also (his initial bid didn't include it), even though it's not even connected in most chargers....at least not now. But I didn't know what the future could hold. It also also for an easy tap of L1 to neutral for unit owners who wanted 120V in their parking stall for e-bikes and such.
 


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When I was receiving bids for my condo association to have our parking garage wired for EVs, I checked a handful of chargers -- they were all L1/L2/GFI. Although the Ford did have neutral listed as "optional." I did end up talking the electrician who took our bid into wiring neutral also (his initial bid didn't include it), even though it's not even connected in most chargers....at least not now. But I didn't know what the future could hold. It also also for an easy tap of L1 to neutral for unit owners who wanted 120V in their parking stall for e-bikes and such.
You have a very DANGEROUS setup here with your L1 & neutral wired to a120v receptacle. First, I don't know how you wired from a #6 size wire down to a #12 to the 120v receptacle but even more DANGEROUS is that your L1 is on a 60 amp breaker and your wiring that over a #12 wire to the 120v receptacle.

I don't know but I would rethink your setup. On a Tesla Wall Connector there is no place to terminate a neutral wire. I hope you aren't using wire nuts inside the WC. That's a no no NO.
 
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You have a very DANGEROUS setup here with your L1 & neutral wired to a120v receptacle. First, I don't know how you wired from a #6 size wire down to a #12 to the 120v receptacle but even more DANGEROUS is that your L1 is on a 60 amp breaker and your wiring that over a #12 wire to the 120v receptacle.

I don't know but I would rethink your setup. On a Tesla Wall Connector there is no place to terminate a neutral wire. I hope you aren't using wire nuts inside the WC. That's a no no NO.
How do you know what gauge wire the electrician used? How do you know what breaker he used? How do you know what the electrician did from the L1/L2/neutral drop to the 120VAC outlet? But whatever (was only replying to Mongo in the first place, who's an even keel sort). Think as you wish.
 
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Why 40A? My calculation is 44A is fine and that’s what I set PowerShare max to….55x.8=44A
I could be wrong, but I don't think you can set the car to charge at 44A, it's either 40 or 50A as your choices. If there's a way to set it to 44A, let me know how to do it so I can change mine.
 

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I could be wrong, but I don't think you can set the car to charge at 44A, it's either 40 or 50A as your choices. If there's a way to set it to 44A, let me know how to do it so I can change mine.
You can't set the Wall Connector itself to 44A. However, I think Group Power Management does allow arbitrary total current levels like 44A.

You can set the car to 44A, but that requires the WC being set too high (48A) and doesn't protect against other cars pulling too much current .
 

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How do you know what gauge wire the electrician used? How do you know what breaker he used? How do you know what the electrician did from the L1/L2/neutral drop to the 120VAC outlet? But whatever (was only replying to Mongo in the first place, who's an even keel sort). Think as you wish.
It is code approved in certain cases to tap branch conductors to an additional breakerand load (but of course, one should not put a 15A receptacle directly on a 50A circuit)

Neutral? None needed. This is only for Tesla Wall Connector, 2 hots and a ground. That's it. 6/2 MC.
Yes, for a branch circuit to a Wall Connector, neutral is not needed. However, that wasn't what you called out:
If you want to do it right run 6/2 MC from main panel to sub panel.
I bring up this point since if the current feed is 6/2, adding a sub panel on the existing cable isn't possible.
 


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60A breaker is code compliant under 240.4(B)



/QUOTE]


That section is specifically referring to an Adjustable trip breaker. Where does it say that is what he is using?

Additionally, 240.4(B)(1) refers to plugs, which are not allowed for Tesla wall chargers. But honestly, this wording is weird, so not sure how to properly interpret it.
 

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I could be wrong, but I don't think you can set the car to charge at 44A, it's either 40 or 50A as your choices. If there's a way to set it to 44A, let me know how to do it so I can change mine.
You don't set the car to 44AMPS (I think you can do that but that is not what you want). You set the max powershare amount to 44AMPS which then only allows the sum of all wall connectors to pull 44AMPS total.....I have 3 wall connectors setup this way such that they can pull either 14amps each, 22Amps each or 44Amps depending on how many cars are charging at once.
This is done through the URL on your smartphone or ipad when connected to the WIFI network for the master wall connector

You can't set the Wall Connector itself to 44A. However, I think Group Power Management does allow arbitrary total current levels like 44A.

You can set the car to 44A, but that requires the WC being set too high (48A) and doesn't protect against other cars pulling too much current .
Correct, I set the total group to 44AMPS
 

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If the Romex is on a 50A breaker at the panel it would still be protected, even if he has 60A at the sub panel but I think you would still be limited to 40A charging because that is your weakest link. I chose to go a step down, I have a 50A on the Romex, I'd rather have it under the rating than slightly over. I know a bunch of people have run it on a 60A and don't have issues, I wasn't willing to take that chance to charge a little bit faster. I charge it overnight anyway, so an extra hour or whatever doesn't matter to me.
Right, but he stated he has a 60a breaker on the 6/2 romex.

Additionally, he has a 60a breaker at the subpanel.

So if he replaces the 60a breaker at the main panel (which he REALLY needs to IMO), then he also needs to change the subpanel breaker to 50a as well, even though subpanel to WC is 6/2mc.
 

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Why 40A? My calculation is 44A is fine and that’s what I set PowerShare max to….55x.8=44A
You are basing your calculation on 6/2 Romex being rated for 55a. However, 6/2 Romex should be on a 50a Breaker, NOT 60a. So you should base your calculation on 50a x .8 = 40a continuous load.
 

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That section is specifically referring to an Adjustable trip breaker. Where does it say that is what he is using?

Additionally, 240.4(B)(1) refers to plugs, which are not allowed for Tesla wall chargers. But honestly, this wording is weird, so not sure how to properly interpret it.
You are basing your calculation on 6/2 Romex being rated for 55a. However, 6/2 Romex should be on a 50a Breaker, NOT 60a. So you should base your calculation on 50a x .8 = 40a continuous load.
240.4
(B) Overcurrent Devices Rated 800 Amperes or Less.
The next higher standard overcurrent device rating (above the ampacity of the conductors being protected) shall be permitted to be used, provided all of the following conditions are met:
(1) The conductors being protected are not part of a branch circuit supplying more than one receptacle for cord-and-plug-connected portable loads.
(2) The ampacity of the conductors does not correspond with the standard ampere rating of a fuse or a circuit breaker without overload trip adjustments above its rating (but that shall be permitted to have other trip or rating adjust‐
ments).
(3) The next higher standard rating selected does not exceed 800 amperes

(1) is satisfied since the circuit is not feeding outlets
(2) is satisfied since 55A does not correspond to a standard breaker that lacks adjustment.
(3) is satisfied since 60A is less than 800A

So a 60A breaker on 6 gauge NM-B is code compliant.
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