[sofakng]

Can anybody tell me if there are any restrictions/requirements or best practices for running the supply wire from a main service panel to an adjacent sub-panel?

Here are my options:

Option #1 and #2 - Sub-panel main lugs at top of panel. Service wire can enter from side of sub panel or bottom. (I'm not sure if option #2 would work because I need to bend the #4 copper from the breaker in the main panel down towards the bottom to exit the panel)



Option #3 - I believe I can rotate the sub-panel "upside-down" (bottom feeding?) so the main lugs are at the bottom. (I'm not sure if option #3 would work because of the same reason as above [I can't bend #4 copper from the breaker in the main and exit the main panel at the bottom])



Here are options #4 and #5:



What is the recommend route for the wire?

(I'm using 4-4-4-6 wire (planning to use 3/4" knockouts) and 60A breaker in main panel. Both panels are Square D QO. The sub-panel is a Square D Model #QO112L125PGC)

 

[Jim Port]

#4 AL is not hard to bend. You could use #6 copper also.

No issue with the lugs at the bottom as long as the breakers operate horizontally.

 

[surferdude2]

You will be in violation of code running cable at that height... in fact, you already have some side entries into that main panel that could be shot down. I've had inspectors tell me anything under 5' was a violation but I think the code may be be anything under 7' needs protection. You have to run the wiring in conduit to comply. It may be one of those "inspector decides" things where "the AHJ has the say." Someone can chime in and correct me if I'm wrong.

Have you considered upsizing the main panel... it might be a better solution.

 

[rjniles]

If by 4-4-4-6 you are talking cable, I would not do that. Run PVC conduit with individual conductors.

Sent from my RCT6A03W13E using Tapatalk

 

[Jim Port]

There is no height limitation. The code does require protection if subject to damage, but that is subjective.

 

[sofakng]

Thanks so much for the responses everybody.

The 4-4-4-6 cable is copper and not aluminum.

Is there any problems with using this route?


It seems like the best option? It seems cleaner if I could enter the side of the sub-panel but I'm not sure if that's allowed or would have enough room to bend the cables into the main lugs?

Also, I was told NOT to use PVC in a home because if it catches fire the fumes are toxic and PVC in a home is actually not allowed in certain code jurisdictions.

 

[rjniles]

What do you think the sheath on your NM cable is made of?

 

[Jim Port]

You don't need #4 copper for 60 amps.

The sheath on NM cable gives off the same toxic gases when burned.

 

[sofakng]

Yes, I purchased #4 (4-4-4-6) copper because it was on clearance at Lowe's and I'd rather over-size in case I want a larger breaker later.

That's a good point about the sheath on the NM cable also having toxic gases when burned.

Do you suggest I run the 4-4-4-6 in PVC then and route it as I described in my previous post?

 

[rjniles]

What is the 4-4-4-6 cable designation? Is it a sheathed cable or 4 wires twisted together?

 

[sofakng]

It's sheathed:

 

[rjniles]

SER cable, conduit not required

 

[sofakng]

Thanks so much again for all of the help.

Here is a picture of the sub panel.



Can I enter using the side using the knock-outs? It seems like plenty of room to bend the cables to the main lugs? (or from the bottom knockout, up the side, and over to the main lugs)

 

[Jim Port]

Side or end, your choice.

Don't forget to add the ground bar.

 

[chetwisner]

It's sheathed:

I see only 3 conductors in that cable. Where did the 4-4-4-6 come from?

 

[sofakng]

Take a look at the top left of the cable and you'll see the #6 bare copper hiding. The angle of the picture just doesn't show it.

Thanks so much for the help everybody. I'll post a picture tomorrow of the finished job so you can give me advice or tell me how bad I did

 

[sofakng]

By the way, if I wanted to upgrade from the 60A breaker, what is the larger size I could use with my 4-4-4-6 copper SER cable?

 

[sofakng]

Not sure why I can't edit my posts?

Anyways, the 4-4-4-6 SER cable is labeled XHHW-2. According to this I can go up to 95 A?

I'm thinking about returning the 60A breaker I was originally going to use in the main panel and go for an 80A instead just in case I need more amps in the sub-panel?

 

[surferdude2]

You can't use that rating for branch circuit breaker selection since the wire lugs on breaker panels and circuit breakers are only good for 75° C. wire. That rating is only valid when using the wires where they have to be derated for high ambient or more than 3 in a conduit.

Using the 75° C. rating, you are good with an 80 amp breaker for #4 copper for a branch circuit.

In addition, just in case... you should check with your inspector since a couple of places I have installed in had the local code that only allowed the 60° C. rating to be used on circuits less than 100 amps. Always good to check up front was my takeoff from that. I doubt you are faced with that but it doesn't hurt to check.

 

[sofakng]

Got it. Thanks again so much!