4 AWG copper feeders for 100 amp sub/distribution panel

Yea or nay?

Thanks in advance.




What is the calculated load on the subpanel? What size breakers protected those feeders?

Not a clue

100 amp


If that feeder serves the entire load of the dwelling, the #4 CU is good for 100 amps. If it only serves a portion of the load it is good for 85 amps. A 90 amp breaker would be the next size up available.

Yes, the load for this unit is what you see in the picture.

So there is a disconnect ahead of this panel? If so why are the neutrals and grounds on the same bus? Is the 4th conductor on the top right of the bar?

The LV transformer should not be there. Not a fan of the tags either.

If there is nothing else in the panel that houses the 100 amp breaker for this panel then the #4 is alright. There needs to be separation of the grounding and grounded conductors in this panel and it need to be supplied with four wires which is a violation as well as the small transformer in the bottom left.