Price for 6/3 and 4/3

[EVer Hopeful]

The ampacity charts clearly state that NM-B (Romex) in 6 gauge is rated for a maximum of 55 amps. Other types of wire, in 6 gauge, depending on the maximum temperature for the application may be rated for higher amperage.

Cerrowire Resources - Ampacity Charts

Thanks, I'm beginning to understand it now

For 6 gauge,
Romex - NM-B is classed as a 60 degC conductor, so is only rated to 55amps
Single conductor - THWN is a 65 degC conductor, so is rated to 65 amps, because it's heat resistant
Single conductor - THHN is a 90 degC conductor, so is rated to 75 amps, because it's a High Heat conductor

and I think the last two are stranded. Interestingly, stranded was a requirement when I installed the mini-split

So if I run some THHN in conduit, do I need to use blue and yellow for the energized conductors?

This is interesting stuff

 

[eagle_eye]

Can use THHN in Conduit, using THHN in a conduit means the conduit can also be smaller I.E a 6/3 UF cable would need 2 inch conduit however if you use 4 x 6 awg THHN in a conduit u can use a 1 inch conduit. Also THHN copper so direct from panel box to wall connecter or a nema plug works fine.

If you opt to go with 6/3 UF Burial Cable which is rated for wet and dry keep in mind you still need a conduit unless you will burry the cable.

 

[Jigglypuff]

So say after he will finish installation and will measure temperature(while charging car) and it is not will be hot it should be OK ? Right?

They don't measure the temperature. They check the specs and calculations then put it together.

 

[jcanoe]

Thanks, I'm beginning to understand it now

For 6 gauge,
Romex - NM-B is classed as a 60 degC conductor, so is only rated to 55amps
Single conductor - THWN is a 65 degC conductor, so is rated to 65 amps, because it's heat resistant
Single conductor - THHN is a 90 degC conductor, so is rated to 75 amps, because it's a High Heat conductor

and I think the last two are stranded. Interestingly, stranded was a requirement when I installed the mini-split

So if I run some THHN in conduit, do I need to use blue and yellow for the energized conductors?

This is interesting stuff

I'm not sure that the color matters. The ground wire can be bare or else have green insulation. Sometimes the ground wire can be the next size smaller gauge. The convention is that the Black and Red wire are carrying power, the white wire is Neutral. If you have to use a different color wire then you can wrap the end of the wire at both ends in a colored electrical tape.

 

[Rocky_H]

For 6 gauge,
Romex - NM-B is classed as a 60 degC conductor, so is only rated to 55amps
Single conductor - THWN is a 65 degC conductor, so is rated to 65 amps, because it's heat resistant
Single conductor - THHN is a 90 degC conductor, so is rated to 75 amps, because it's a High Heat conductor

Yes--there ya go. Because of the way they are packaged and insulated and the installation methods used for each type, they have different maximum allowed temperature ratings that each corresponds to a max allowed amps per each wire gauge size. So you saw it there, that for the NM-B type, that can only allow up to 55A, but the THWN type can go up to 65A. So you can see which would be allowed high enough to support a 60A circuit.

I'm not sure that the color matters. The ground wire can be bare or else have green insulation. Sometimes the ground wire can be the next size smaller gauge. The convention is that the Black and Red wire are carrying power, the white wire is Neutral. If you have to use a different color wire then you can wrap the end of the wire at both ends in a colored electrical tape.

yes, I've read the section on it, and the ground and the neutral have pretty specific conditions, but the hot lines are allowed to have a very wide array of colors.

 

[EVer Hopeful]

Ok, I've done a load calculation and I can get a 1430 hanging off the subpanel in the tool shed. That's attached to the main panel with 6/3 that I'm assuming is NM-B (it's hard to read the writing on the jacket) through a 50A breaker. I figured it could come off the sub panel through a 30A GFCI breaker with 8 gauge THHN through metal conduit to the 1430 and maybe use 10 gauge THHN for the ground. Total run in that conduit would be ~20 ft

Does that sound feasible?

Would a 1450 be too much for that setup? - Is 50A even necessary? from what I've read, 50A would be nice, but 30A is more than sufficient to charge for daily driving

If that set up was to be installed, would the conduit need to be metal, or could grey PVC be used? Regardless, what diameter would that conduit need to be? One inch sounds a little excessive, but I understand conduit size is important for heat dissipation


---I said 10 gauge for the ground because Lowe's has some green that should be about long enough sitting in the clearance pile and I read somewhere that the ground can be one gauge smaller

TIA

 

[Jigglypuff]

Ok, I've done a load calculation and I can get a 1430 hanging off the subpanel in the tool shed. That's attached to the main panel with 6/3 that I'm assuming is NM-B (it's hard to read the writing on the jacket) through a 50A breaker. I figured it could come off the sub panel through a 30A GFCI breaker with 8 gauge THHN through metal conduit to the 1430 and maybe use 10 gauge THHN for the ground. Total run in that conduit would be ~20 ft

Does that sound feasible?

Would a 1450 be too much for that setup? - Is 50A even necessary? from what I've read, 50A would be nice, but 30A is more than sufficient to charge for daily driving

If that set up was to be installed, would the conduit need to be metal, or could grey PVC be used? Regardless, what diameter would that conduit need to be? One inch sounds a little excessive, but I understand conduit size is important for heat dissipation


---I said 10 gauge for the ground because Lowe's has some green that should be about long enough sitting in the clearance pile and I read somewhere that the ground can be one gauge smaller

TIA

Either have an electrician do it or draw up plans and take it to the county/city department for approval. Local code + national code + your specific situation.

 

[Rocky_H]

Ok, I've done a load calculation and I can get a 1430 hanging off the subpanel in the tool shed. That's attached to the main panel with 6/3 that I'm assuming is NM-B (it's hard to read the writing on the jacket) through a 50A breaker.

It is not allowed to have the breaker be a higher rating than the outlet type, so if you are going to do a 14-30 outlet, you should do a 30A breaker. And yes, I think that's totally sufficient for most people's use.

 

[EVer Hopeful]

Thanks for the response.

Makes sense - Perhaps I could do the 30A breaker in the subpanel, with the subpanel connected to a 50A breaker in the main panel?

This is really interesting stuff, I'm reading about conduit now and I see that the maximum fill for three wires or more is 40% of the conduit


I found a calculator on the Southwire website that says:
four 8 gauge conductors are 27% of a 3/4" conduit
four 10 gauge conductors are 15% of a 3/4" conduit

Next comes the number of bends apparently

 

[Vin_L]

I just purchased 6/2 copper at Lowe’s and paid $1.70 a foot. Wired up my Wall Charger this weekend to a 50A breaker.