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Gen 3 Wall Connector Wire and Conduit Question

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The above is rated for 55A so please do not use for a 60A breaker to get 48A charge from the Gen3 HPWC. Even though it won’t draw more than 48A it is not rated to match the breaker you will install so it will not be to code. And someone down the road with try to use something that can draw 60A and could cause a lot of damage.

The wire is good for a 50A breaker to draw 40A for charging. Pairs well with 14-50.
This is confusing. The large majority of Tesla Gen 3 wall charge installs described online or demonstrated on YouTube all use 6 AWG cable when run on a 60 amp breaker. Are they all out of code?
 
Is there any reason not to use UF cable rather than Romex (ie, NM)? I’m finding that the flat cable is surprisingly cheaper today… probably due to all of the supply chain problems. Thx for any insights here. Yes I am using an electrician but want to ensure I am an educated consumer.
 
It is a good idea to refer to the Ampacity charts (thank you Cerro Wire): Cerrowire Resources - Ampacity Charts

The maximum amperage for 6 gauge NM-B, UF-B (only rated for up to 60C) is 55 amps so you shouldn't use these wire types with a 60A circuit.

The maximum amperage for 6 gauge THHN (rated for up to 90C) is 75 amps, so you can use 6 gauge THHN with a 60 amp circuit with no concern.

(6 gauge NM-B (also 6 gauge UF-B) and 8 gauge THHN have the same maximum amperage rating of 55 amps; these should only be used with a maximum 50 amp rated circuit and never with a 60 amp rated circuit.)
 
It is a good idea to refer to the Ampacity charts (thank you Cerro Wire): Cerrowire Resources - Ampacity Charts

The maximum amperage for 6 gauge NM-B, UF-B (only rated for up to 60C) is 55 amps so you shouldn't use these wire types with a 60A circuit.

The maximum amperage for 6 gauge THHN (rated for up to 90C) is 75 amps, so you can use 6 gauge THHN with a 60 amp circuit with no concern.

(6 gauge NM-B and 8 gauge THHN have the same maximum amperage rating of 55 amps; should only be used with a maximum 50 amp rated circuit.)
Ok that’s interesting since 1) most things I read say that you are allowed to round up from 55 amp breaker to 60 since there are no 55 amp breakers and 2) since the maximum amp load of the G3 wall charger is 48 amps, should be fine anyway with the 6 gauge romex on the 60 amp breaker. Not saying you are wrong just trying to square what you are advising with other things I have read.
 
Ok that’s interesting since 1) most things I read say that you are allowed to round up from 55 amp breaker to 60 since there are no 55 amp breakers and 2) since the maximum amp load of the G3 wall charger is 48 amps, should be fine anyway with the 6 gauge romex on the 60 amp breaker. Not saying you are wrong just trying to square what you are advising with other things I have read.
I will defer to someone with more experience regarding the rounding rule.

Found this - see post #174: Anyone use this Romex 6/3 cable during install?

"You are allowed to round up on the breaker since they don’t make a 55A to protect the wire in the event of a short. It’s still a 55A circuit. But you need to round down on the load since you can’t set the load to 55A. So yeah set HPWC to 50A."
 
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I will defer to someone with more experience regarding the rounding rule.

Found this - see post #174: Anyone use this Romex 6/3 cable during install?

"You are allowed to round up on the breaker since they don’t make a 55A to protect the wire in the event of a short. It’s still a 55A circuit. But you need to round down on the load since you can’t set the load to 55A. So yeah set HPWC to 50A."
#6 THHN in conduit - perfectly fine and meets code for 60a breaker.

#6 NM-B (romex) - not fine for 60a breaker. Needs to be 50a breaker to meet code. If you round up to the next size (in code), that would be 55a, not 60a. Do not use 6 gauge romex on a 60a breaker.
 
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Correct. (Related; NM-B can be installed in conduit, should only be used in conduit where the wiring needs to be protected.)
Ok ty — one last question — is there any difference between using the standard round romex vs the flat UF type cable, which is flat and wider but coming up cheaper today for the same 4/3 copper configuration. Ty
 
Ok ty — one last question — is there any difference between using the standard round romex vs the flat UF type cable, which is flat and wider but coming up cheaper today for the same 4/3 copper configuration. Ty
That's a new one for me. I thought NM was not allowed in conduit. Maybe I'm not looking at the right NEC table, but I sure don't see NM on it.
 
To the prior poster's point, I believe you need to be sure to use the right size conduit. If I am running NM 4/3 through my basement ceiling "unprotected" (ie, not in conduit) as is legal for an unfinished basement, and next I run it through the wall where it emerges into the garage, I need to run it in conduit for the last 10 feet along the inside of the garage wall to the G3 Tesla Wall Charger. My question is, what type and size of conduit would you recommend using? I cannot seem to find anything that indicates what size conduit is necessary in this situation. Again, I am not doing this myself but I want to ensure it is done correctly. TY
 
To the prior poster's point, I believe you need to be sure to use the right size conduit. If I am running NM 4/3 through my basement ceiling "unprotected" (ie, not in conduit) as is legal for an unfinished basement, and next I run it through the wall where it emerges into the garage, I need to run it in conduit for the last 10 feet along the inside of the garage wall to the G3 Tesla Wall Charger. My question is, what type and size of conduit would you recommend using? I cannot seem to find anything that indicates what size conduit is necessary in this situation. Again, I am not doing this myself but I want to ensure it is done correctly. TY
Found this table but it is for THHN not NM-B: Conduit Fill Table - PVeducation.com
 
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So far as I am aware, NM is not acceptable in conduit. It must be thhn or equivalent. Sheathed cable and conduit is not code compatible. You can use NM in some areas, or thhn in conduit, but switching between them without proper transitions is also not code compatible.

In other words, thhn or equivalent in conduit, NM in open air possible, but transitions must be in an accessible junction box with appropriate connectors.

For code anyway...
 
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So far as I am aware, NM is not acceptable in conduit. It must be thhn or equivalent. Sheathed cable and conduit is not code compatible. You can use NM in some areas, or thhn in conduit, but switching between them without proper transitions is also not code compatible.

In other words, thhn or equivalent in conduit, NM in open air possible, but transitions must be in an accessible junction box with appropriate connectors.

For code anyway...
NM-B is completely acceptable and in code to put in conduit. But only needs to be used when exposed and needing physical protection - like in a garage.

It just sucks to pull a long distance. So limit the length needed in conduit for your own sanity.
 
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After much research I have concluded that using MC 4/3 (Copper wire/aluminum jacket) makes the most sense all around. It’s much cheaper than 4/3 romex and can be run compliant to code without conduit anywhere. Not sure why no one uses this in any of the install videos but it seems to make the most sense — am I missing something? Ty
 
After much research I have concluded that using MC 4/3 (Copper wire/aluminum jacket) makes the most sense all around. It’s much cheaper than 4/3 romex and can be run compliant to code without conduit anywhere. Not sure why no one uses this in any of the install videos but it seems to make the most sense — am I missing something? Ty
If you are only installing a wall connector, you can use 4/2 instead. It’s one fewer large wire to have to pay for and install/pull. You do not need a neutral at all. You only need two hots and a ground. You will cap off the neutral anyways. Probably better to not even pay for one.
 
After much research I have concluded that using MC 4/3 (Copper wire/aluminum jacket) makes the most sense all around. It’s much cheaper than 4/3 romex and can be run compliant to code without conduit anywhere. Not sure why no one uses this in any of the install videos but it seems to make the most sense — am I missing something? Ty
My electrician used metallic clad (MC) wire; 70 ft of it from my panel to my garage. MC can't be used underground or outdoors or in wet/damp environments. MC can be used in attic spaces, inside walls and inside a garage.

Always wear gloves when working with MC or you will cut yourself on the cladding.
 
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If you are only installing a wall connector, you can use 4/2 instead. It’s one fewer large wire to have to pay for and install/pull. You do not need a neutral at all. You only need two hots and a ground. You will cap off the neutral anyways. Probably better to not even pay for one.
Ty. Is there a minimum wire size for the ground?