6/3 or 4/3 on 60amps

[shadow4478]

It’s unreal how much disagreement there is across every thread on if you can use 6/3 wire on 60amp beaker pulling 48amp constant. I spoke with 2 licensed electricians both instantly said 6/3 wire.
Both have done man had them some inspected and all passed, seems like a simple answer and yet all the counter arguments using 4/3 also have validity.
I think if you put 10 electricians the ESA all electricians there would be a ton of controversy.

Here something I can’t get an answer right now, maybe someone knows,
What wire to use romex, armoured cable or THHN
I’m going from BSMt panel directly into garage and need to run 38’ to other side of garage to the outside next to my HYDRO meter, I’m able to run all ever cable through the garage studs, do I still need conduit?

 

[ewoodrick]

The quicker someone answers, the less trust that I have in them, unless they do this for a living, which most electricians don't.

But no matter what they say, the code is the code. And the code is based on safety factors.

If you aren't sure, then lean with the safest solution. Going beyond code is great, going below code is deadly.

Get someone to show you the code.

 

[MattM24]

It’s unreal how much disagreement there is across every thread on if you can use 6/3 wire on 60amp beaker pulling 48amp constant. I spoke with 2 licensed electricians both instantly said 6/3 wire.
Both have done man had them some inspected and all passed, seems like a simple answer and yet all the counter arguments using 4/3 also have validity.
I think if you put 10 electricians the ESA all electricians there would be a ton of controversy.

Here something I can’t get an answer right now, maybe someone knows,
What wire to use romex, armoured cable or THHN
I’m going from BSMt panel directly into garage and need to run 38’ to other side of garage to the outside next to my HYDRO meter, I’m able to run all ever cable through the garage studs, do I still need conduit?

6/3 NMD90 is fine. You’re in Canada.

6/3 NM-B (Romex they sell in the USA) is not ok.

I ran 6/3 NMD90 through the basement (protected) and switched to EMT on the garage wall with #6 R90 in it. You need a JB or disconnect to join the two.

 

[MattM24]

If you’re protected like it sounds like you might be, you could run the NMD90 the whole way.
What did the Electricians suggest?

 

[dogmodes]

It’s unreal how much disagreement there is across every thread on if you can use 6/3 wire on 60amp beaker pulling 48amp constant. I spoke with 2 licensed electricians both instantly said 6/3 wire.
Both have done man had them some inspected and all passed, seems like a simple answer and yet all the counter arguments using 4/3 also have validity.
I think if you put 10 electricians the ESA all electricians there would be a ton of controversy.

Here something I can’t get an answer right now, maybe someone knows,
What wire to use romex, armoured cable or THHN
I’m going from BSMt panel directly into garage and need to run 38’ to other side of garage to the outside next to my HYDRO meter, I’m able to run all ever cable through the garage studs, do I still need conduit?

There really isn’t a disagreement, the code is the code. 6/3 isn’t the issue, it’s 6/3 nm-b romex that’s the problem. I agree a lot of electricians may install it or say it’s fine for a 60amp circuit, which it is allowed when you’re talking about ovens and such. But if you’re talking about car chargers, which is pulling full loads for a long period of time they have different rules. It’s the insulation heat requirements that is the issue, THHN in conduit or armored cable have higher temp thresholds so 6awg in conduit/greenfield is what you should use. It will work and yeah probably be fine with romex, still shouldn’t do it though at 48amp. I have THHN in conduit but still only run at 40A charge, just because I’m in no rush and have an already pretty big electric load.

 

[Cosmacelf]

I don’t recall any discussion on these forums about Canadian electrical codes on this matter. Canadian code is different from US code. The other posters point out that Canadian NMD90 6 gauge is rated for 60A (actually, it seems rated for up to 75A according to this: NMD90 Romex® SIMpull® Copper | Southwire).

Since you are talking 48A, I presume you are connecting a Wall Connector, in which case all you need is 6/2, not 6/3. And again, this all assumes the wire isn’t in danger of being directly exposed to wet weather, in which case you would need wet weather conduit. But assuming it is a dry install, unconduitted 6/2 NMD90 looks like it’ll work just fine.

 

[Cosmacelf]

There really isn’t a disagreement, the code is the code. 6/3 isn’t the issue, it’s 6/3 romex that’s the problem. I agree a lot of electricians may install it or say it’s fine for a 60amp circuit, which it is allowed when you’re talking about ovens and such. But if you’re talking about car chargers, which is pulling full loads for a long period of time they have different rules. It’s the insulation heat requirements that is the issue, THHN in conduit or armored cable have higher temp thresholds so 6awg in conduit/greenfield is what you should use. It will work and yeah probably be fine with romex, still shouldn’t do it though at 48amp. I have THHN in conduit but still only run at 40A charge, just because I’m in no rush and have an already pretty big electric load.

The OP lives in Canada, so isn’t subject to US electrical code. They have a different code there and even different products.

 

[MattM24]

There really isn’t a disagreement, the code is the code. 6/3 isn’t the issue, it’s 6/3 romex that’s the problem. I agree a lot of electricians may install it or say it’s fine for a 60amp circuit, which it is allowed when you’re talking about ovens and such. But if you’re talking about car chargers, which is pulling full loads for a long period of time they have different rules. It’s the insulation heat requirements that is the issue, THHN in conduit or armored cable have higher temp thresholds so 6awg in conduit/greenfield is what you should use. It will work and yeah probably be fine with romex, still shouldn’t do it though at 48amp. I have THHN in conduit but still only run at 40A charge, just because I’m in no rush and have an already pretty big electric load.

6/3 romex is not the problem. The problem is that 6/3 romex in Canada where the Op is from is not the same as 6/3 romex in the US where you are from.

6/3 Romex in Canada is NMD90 and is rated for 65A at 75C which all connections in this system are rated.

6/3 Romex in the US is NM-B and is rated for only 60C, which puts it at a limit of 55A and therefore not good enough for a 60A circuit.

THHN is also not in Canada. We have T90 and R90.

 

[dogmodes]

The OP lives in Canada, so isn’t subject to US electrical code. They have a different code there and even different products.

Yeah I didn’t notice the CA, had just edited my post to say I meant nm-b romex and then noticed yourr reply. No clue what nmd90 is or what its temp rating is.

 

[dogmodes]

6/3 romex is not the problem. The problem is that 6/3 romex in Canada where the Op is from is not the same as 6/3 romex in the US where you are from.

6/3 Romex in Canada is NMD90 and is rated for 65A at 75C which all connections in this system are rated.

6/3 Romex in the US is NM-B and is rated for only 60C, which puts it at a limit of 55A and therefore not good enough for a 60A circuit.

THHN is also not in Canada. We have T90 and R90.

Man you guys are quick lol, I edited my post to say nm-b in like 60 seconds from post.

 

[MattM24]

I don’t recall any discussion on these forums about Canadian electrical codes on this matter. Canadian code is different from US code. The other posters point out that Canadian NMD90 6 gauge is rated for 60A (actually, it seems rated for up to 75A according to this: NMD90 Romex® SIMpull® Copper | Southwire).

Since you are talking 48A, I presume you are connecting a Wall Connector, in which case all you need is 6/2, not 6/3. And again, this all assumes the wire isn’t in danger of being directly exposed to wet weather, in which case you would need wet weather conduit. But assuming it is a dry install, unconduitted 6/2 NMD90 looks like it’ll work just fine.

It’s only rated to 75A in a 90C system.
Residential breakers are 60C/75C rated and not 90C rated, so that 75A rating is only good for derating purposes.

 

[MattM24]

Man you guys are quick lol, I edited my post to say nm-b in like 60 seconds from post.

It’s a common problem here. I try and get the word out so other Canadians know.
There are not a lot of us compared to the US, so Canadian content gets lost in here.

 

[fholbert]

Yeah I didn’t notice the CA, had just edited my post to say I meant nm-b romex and then noticed yourr reply. No clue what nmd90 is or what its temp rating is.

Here I thought CA was California...

 

[Cosmacelf]

Here I thought CA was California...

View attachment 948273

Weird forum behavior. It can mean either California or Canada. I recognized the city as being in Canada, and not in California.

 

[Rice&Curry]

To settle the controversy you can get the city to inspect and approve the installation. yes, it will cost some money, but your insurance claim if ever there is a fire will never get denied.

 

[shadow4478]

If you’re protected like it sounds like you might be, you could run the NMD90 the whole way.
What did the Electricians suggest?

The electrician suggested 6/3 romex as I’m going through studs in the garage he said no conduit needed as long as the wire can go through Center of each 2x4 small conduit needed at the very end to go out of garage right into the charger.
He did say armoured 6/3 or romex in conduit if we can’t go through the studs.

Edit: when you say protected, does running through the studs qualify ? You’d be able to touch it where it comes out of the basement and where it exits the the garage to the outside into the charger, the the 6/3 romex would be between the studs/2x4 drilled through each one. (It’s a dry garage)

And yes Canada not California

 

[MattM24]

The electrician suggested 6/3 romex as I’m going through studs in the garage he said no conduit needed as long as the wire can go through Center of each 2x4 small conduit needed at the very end to go out of garage right into the charger.
He did say armoured 6/3 or romex in conduit if we can’t go through the studs.

Edit: when you say protected, does running through the studs qualify ? You’d be able to touch it where it comes out of the basement and where it exits the the garage to the outside into the charger, the the 6/3 romex would be between the studs/2x4 drilled through each one. (It’s a dry garage)

And yes Canada not California

Make sure your Electrician gets it permitted with ESA and they’ll make sure it’s right.

My meaning of protected is irrelevant to the ESA Inspector.

 

[Cosmacelf]

Whatever you do, use 6/2 not 6/3 or else you’ll have an extra wire for no reason.

And yes, romex through studs is fine, surface mount romex isn’t. For that you’d use MC cable.

 

[shadow4478]

Make sure your Electrician gets it permitted with ESA and they’ll make sure it’s right.

My meaning of protected is irrelevant to the ESA Inspector.

And the 6/3 is mainly for thicker ground over 38’ 6/2 would be cheaper but the 1mm ground not sure about.

Was hoping to do it myself both electricians are friends.
But yes I’ll look further Into rules possibly add part conduit. Where it’s touchable.

Thank you for all the help
I had no idea that US code and cable built was so different
I read so many posts satating 4/2 or 4/3 wire.

 

[shadow4478]

Whatever you do, use 6/2 not 6/3 or else you’ll have an extra wire for no reason.

And yes, romex through studs is fine, surface mount romex isn’t. For that you’d use MC cable.

Great things are lining up with electricians suggestions,
Not sure how thick the ground is on 6/2 but I’m sure it’s fine it would be easier to pull 6/2 was thinking of using the the 3rd wire as ground if thicker.