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Wiring question

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krishb

New Member
Aug 29, 2018
1
0
Ohio
I have my main panel in my garage. For the time being I wanted to get a 50 amp breaker installed in the panel and then run #4-3 wire to a junction box in my garage. From there I wanted my electrician to run a #6 wire for a NEMA 14-50 outlet. My plan is to use the 14-50 outlet for the time being and later upgrade the breaker to a higher amp later for a dual Tesla HPWC setup if I get another Tesla.

I had an electrician come earlier today for a quote. He said it is against the code to use #4 and #6 in the junction box. I see a number of people suggesting to use #4 from the main panel to for later flexibility. I am confused now. So, should I be only using only #4 everywhere. Also, if I have the junction box, can I wire to a second NEMA 14-50 outlet, assuming I use only one a time?
 
I have my main panel in my garage. For the time being I wanted to get a 50 amp breaker installed in the panel and then run #4-3 wire to a junction box in my garage. From there I wanted my electrician to run a #6 wire for a NEMA 14-50 outlet. My plan is to use the 14-50 outlet for the time being and later upgrade the breaker to a higher amp later for a dual Tesla HPWC setup if I get another Tesla.

I had an electrician come earlier today for a quote. He said it is against the code to use #4 and #6 in the junction box. I see a number of people suggesting to use #4 from the main panel to for later flexibility. I am confused now. So, should I be only using only #4 everywhere. Also, if I have the junction box, can I wire to a second NEMA 14-50 outlet, assuming I use only one a time?


My understanding as long as the breaker protecting the circuit is at the lowest ampacity of the wiring involved you are fine? I'm not an electrician though. You also aren't saving very much money dropping to the 6 wire for the second half.
 
I had an electrician come earlier today for a quote. He said it is against the code to use #4 and #6 in the junction box. I see a number of people suggesting to use #4 from the main panel to for later flexibility.
I am wondering if there is some miscommunication somewhere, as far as what you are describing here or what the electrician is talking about, or something. It is very commonly done to do a thicker wire run to a junction box and do a smaller run out of that. I agree with @jdcollins5 to ask specifically what he thinks is wrong with it.
 
I would ask the electrician to give you the Code Article he is quoting from.

I have not seen anywhere in the code that this is disallowed, but it would not surprise me in the least if it was not allowed.

The danger I see would be someone coming along later and seeing 4awg and being like "oh, I can change this up to a 70a breaker", etc... I wish I understood the code in depth enough to give an authoritative answer.

One idea here that is common would be to take that 4awg (or even larger - you could consider aluminum) to an electrical panel in the garage and then do branch circuits off of that for receptacles or wall connectors. That gives you the most flexibility and it may provide for disconnect requirements, etc... (you can do one 14-50 and one wall connector for instance...)

Anyway, just food for thought!

If it was NEC code legal to do it, you would need connectors that let you splice 4awg to 6awg. I don't think there are any wire nuts that would support this.
 
I have not seen anywhere in the code that this is disallowed, but it would not surprise me in the least if it was not allowed.

The danger I see would be someone coming along later and seeing 4awg and being like "oh, I can change this up to a 70a breaker", etc... I wish I understood the code in depth enough to give an authoritative answer.

One idea here that is common would be to take that 4awg (or even larger - you could consider aluminum) to an electrical panel in the garage and then do branch circuits off of that for receptacles or wall connectors. That gives you the most flexibility and it may provide for disconnect requirements, etc... (you can do one 14-50 and one wall connector for instance...)

Anyway, just food for thought!

If it was NEC code legal to do it, you would need connectors that let you splice 4awg to 6awg. I don't think there are any wire nuts that would support this.

Splices with this size wire is typically done with split bolts and tape.