Does wall charger ground need to be insulated?

[Lee Miller]

I am installing a wall mounted charger with 60A breaker and #6 live cables. Is is there any reason the number 10 ground needs to be insulated?

 

[GlazedHam]

NEC 250.118 (1) and 250.119 are where your awnser are but this assumes you are in a location that follows NEC and does not have a local law or regulation that supersede that. Generally the rule of thumb with electrical work is if you don't know what you are doing and don't know how to look things up in the NEC you probably should be hiring a electrician.

 

[Lee Miller]

There's nothing in common sense or regs that I can see, but I'm puzzled by why the Tesla installation depicts it that way.

 

[Gauss Guzzler]

No need for ground insulation. As for the manual illustrations:

1. The green wire is more clearly depicted in graphics
2. Early chargers used 100A circuits requiring 8 AWG ground which typically needs to be stranded, and thus needs to be insulated for safe pulling

 

[stopcrazypp]

There's nothing in common sense or regs that I can see, but I'm puzzled by why the Tesla installation depicts it that way.

Only needed a short section for my 14-50 installation, so price didn't really matter to me, but at Lowes the THHN costs less than Home Depot, so the price difference (at least here in California) is only 60 cents for bare solid vs 68 cents a foot for green THHN:
Southwire (By-the-Foot) 10-Gauge Solid SD Bare Copper Grounding Wire 10626090 - The Home Depot
https://www.lowes.com/pd/Southwire-10-AWG-Stranded-Green-Copper-THHN-Wire-By-the-Foot/3135091

The stranded wire is much easier to work with, so I would pick it any day for that 13% more cost (even if you are buying 100ft, that's only $8 difference).

If instead you were buying it in a bundle with the ground wire included that's obviously a different case (those the ground usually come bare). Note if you are using a 60 amp breaker you can't use 6 gauge Romex (which is only rated for 55A breaker), you should use THHN if you are doing 6 gauge.

 

[Lee Miller]

No need for ground insulation. As for the manual illustrations:

1. The green wire is more clearly depicted in graphics
2. Early chargers used 100A circuits requiring 8 AWG ground which typically needs to be stranded, and thus needs to be insulated for safe pulling

Ah ha -- that makes sense. I didn't know the history. Thanks.

 

[Lee Miller]

Only needed a short section for my 14-50 installation, so price didn't really matter to me, but at Lowes the THHN costs less than Home Depot, so the price difference (at least here in California) is only 60 cents for bare solid vs 68 cents a foot for green THHN:
Southwire (By-the-Foot) 10-Gauge Solid SD Bare Copper Grounding Wire 10626090 - The Home Depot
https://www.lowes.com/pd/Southwire-10-AWG-Stranded-Green-Copper-THHN-Wire-By-the-Foot/3135091

The stranded wire is much easier to work with, so I would pick it any day for that 13% more cost (even if you are buying 100ft, that's only $8 difference).

If instead you were buying it in a bundle with the ground wire included that's obviously a different case (those the ground usually come bare). Note if you are using a 60 amp breaker you can't use 6 gauge Romex (which is only rated for 55A breaker), you should use THHN if you are doing 6 gauge.

THHN and I was mainly debating ease of pulling (about 60 ft and a few bends) overlooking the stranded option for #10. Thanks for the advice.