Wire Guage clarification help.

[diehlryan]

Thank you for replying.

We are Neighbors, I live just behind the village. I will keep and eye out for your vehicles.

Yes, I know the manual specifies 6AWG, many are using 6/2 AWG romex, but that has a maximum of 55Ampacity. While it should be fine, my understanding is that it does not meet code.

When is your delivery date?

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[dradam]

When is your delivery date?

R1S la silver 21 OC September/October 2023 as of the last delivery estimate.

 

[supernu8]

I can do anything I want because the panel is in an unfinished area and I have a straight shot to a column I built in the middle of the garage that will hold the charger.

Since you are installing in an unfinished area, I would run a 3/4" metal or PVC conduit with 2x #6THHN and a #10 ground with a 60A breaker. This removes any questions about proper sizing and gives you 48A charging if you need it.
You could use liquidtite or flex but it may be harder to pull wire and to attach without looking sloppy.
Exposed romex in a garage is a good target for sharp edged tools and ladders.

 

[dradam]

Since you are installing in an unfinished area, I would run a 3/4" metal or PVC conduit with 2x #6THHN and a #10 ground with a 60A breaker. This removes any questions about proper sizing and gives you 48A charging if you need it.
You could use liquidtite or flex but it may be harder to pull wire and to attach without looking sloppy.
Exposed romex in a garage is a good target for sharp edged tools and ladders.

Thanks Supernu8,

Yes the consensus is 6AWG THHN -- the type of conduit may depend on what my dealers have in stock. I was thinking 3x 6 AWG leads plus ground in case a neutral is ever needed in the future, but I know of no EVSE's that require a neutral.

 

[Zoidz]

Thank You Jeeden, I have considered a 40 ft run of Liquid tight conduit and may still go that way. Although I have had trouble finding information on heat and its affect in liquid tight or even hard PVC conduit. I focused on the Flexible metal only because I can by it with all the connectors in it.

The Idea of future sizing the conduit is great, but My Sub panel could not support another breaker. If we one day go with two EV's I may switch to a single load shaing charger with Two cables such as the Grizzl-E.

Many thanks for chiming in.

I use EMT for home projects like this. It's relatively cheap, cuts with a hacksaw, easy to install and support, and Lowes and Home Cheapo have all the fittings, including 90 degree bends, on hand. You could use flex where you have bends as well. 3/4" is fine, allowing up to 4 #6 conductors. I would pull a neutral for future proofing.

If you use flex, you should run a ground conductor. Properly installed, EMT can be the ground path. However, flex can be the ground path only when less than 6 feet long.

 

[dradam]

I use EMT for home projects like this. It's relatively cheap, cuts with a hacksaw, easy to install and support, and Lowes and Home Cheapo have all the fittings, including 90 degree bends, on hand. You could use flex where you have bends as well. 3/4" is fine, allowing up to 4 #6 conductors. I would pull a neutral for future proofing.

If you use flex, you should run a ground conductor. Properly installed, EMT can be the ground path. However, flex can be the ground path only when less than 6 feet long.

 

[dradam]

Thank you Zoids,

Yes I will likely run a future proofing neutral and definitly a dedicated ground. Conduit/flex not sure yet. My run is short but will have about 4 bends. Sub panel up then right/left/down/back of charger.

 

[Mikebike97]

You can't run 6 AWG Romex (NM-B in the chart below) which is rated for 55amps off a 60amp breaker, as the breaker can't have a higher trip rating than the circuit wire max capacity for obvious reasons (think of a short circuit which would allow 60amps to run through the 55amp rated wire).

4 AWG Romex would probably be easier to run then installing conduit and pulling 3 or 4 THHN cables through it depending on how many twists and turns it makes.

It's a little concerning that the electrician was willing to install a 60 amp breaker on 55amp rated cable because "it will not exceed 48 amp load".. well accidents happen and that's why we use breakers in the first place. Secondly, a 55 amp rated 6 AWG Romex cable needs to be derated by 20% under "continuous load" (which is how our EVSE's are classified) so that would be 44 amps max load, not 48 amps on that 6 AWG Romex.

I would echo what osmobilemike said.
Seems you need to check this electricians license.
Also, many of the cheaper 50 amp outlets have contacts that are poorly made. I recommend at a minimum high end NEMA 14-50, unless your electrician is hardwiring it.

 

[dradam]

I would echo what osmobilemike said.
Seems you need to check this electricians license.
Also, many of the cheaper 50 amp outlets have contacts that are poorly made. I recommend at a minimum high end NEMA 14-50, unless your electrician is hardwiring it.

Thank you Mike,
The charger install will be hard wired. People here have been extremely helpful. The run will be THHN 6AWG, The conduit to be determined.

 

[dradam]

Here I go again,

Electrician asked me to speak to his supplier to clarify wire size. Supplier says 6AWG THHN is rated to 55 ampacity and for 48 A charging I need to go to 4AWG.

Here on the forum people have said that while the charger block may accept 4AWG The connection block is spec'd for 6AWG so don't do it.

Here People have said that 6 AWG THHN in conduit IS ok .

What am I missing? (and please don't say an electrician)

My current presumptive plan is 6AWG THHN in a flexible PVC Conduit. I an seeing that 6AWG ampacity is 65A and with a 20 percent derating for safety sould be fine carrying 52 A .

Thanks again in advance.

 

[Donald Stanfield]

What I don't understand is there is Romeo 6 gauge with a stamped 90C rating right on it, but the code is apparently saying it's not rated for 90C. If it is rated for 90C, isn't it the same as THHN rating wise?

NVM even in Romex's official charts it is derated to 60c

 

[dradam]

What I don't understand is there is Romeo 6 gauge with a stamped 90C rating right on it, but the code is apparently saying it's not rated for 90C. If it is rated for 90C, isn't it the same as THHN rating wise?

NVM even in Romex's official charts it is derated to 60c

Yes Donald, Super confusing.

 

[godfodder0901]

What I don't understand is there is Romeo 6 gauge with a stamped 90C rating right on it, but the code is apparently saying it's not rated for 90C. If it is rated for 90C, isn't it the same as THHN rating wise?

NVM even in Romex's official charts it is derated to 60c

Pretty sure the conductors themselves aren't the issue, it's the jackets that cause the derating.

 

[Donald Stanfield]

Pretty sure the conductors themselves aren't the issue, it's the jackets that cause the derating.

Okay but doesn't that basically mean the same thing from a usability perspective? You can't use it because it can't handle the 90c required if I'm understanding it correctly. Don't get me wrong I'm not trying to correct you or anything I legitimately am confused about the whole thing.

 

[godfodder0901]

Okay but doesn't that basically mean the same thing from a usability perspective? You can't use it because it can't handle the 90c required if I'm understanding it correctly. Don't get me wrong I'm not trying to correct you or anything I legitimately am confused about the whole thing.

I think we are saying the same thing. The conductor can handle the 90c, but the jacket can't, so we use 60c.

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