This panel (Square D Hom612L100) has 4 slots. Is it possible to make one of them serve as the main breaker?

  • 1
    Six, but it's still a cripplingly small panel. People always want more power later, so you're better off using a much larger panel (12/16?) for versatility. Mar 20, 2019 at 16:32

2 Answers 2


You can do this, but it burns up two panel spaces in the process

While the HOM612L100 is a Main Lug Only panel and thus cannot accept a QOM main frame breaker, it can be fitted with a main breaker. How? By backfeeding the panel's busses via a two-pole Homeline branch breaker that is held down with a HOM1RK hold-down kit, as required by NEC 408.36. As a result, the incoming hot wires go onto the lugs of this held-down breaker, and the main lugs can be left unused, or used as feed-through lugs in case expansion is called for.

Note that this requires the main breaker to be a regular (or triplex/quadruplex) Homeline branch breaker, not a GFCI or AFCI (they cannot be backfed as it would damage their electronics), and also costs two panel spaces in what is already a tiny panel; depending on your application, moving up to say a 12-space panel that accepts a main frame breaker may be a better solution as a result.


If it's the same as what I'm seeing on Home Depot's website, I'm going to say no.

A main would serve to cut power to the hot busses in the panel. As I can't actually see what the inner parts of the panel look like, I'm inclined to say that it's probably just an always-on sort of thing. If you want a main for it, get a service disconnect to go between that panel and the utility feed.

  • 1
    This is actually incorrect Mar 19, 2019 at 23:48
  • Care to elaborate? Rather than just blatantly calling it wrong, some constructive detail would be beneficial for everyone.
    – Skudd
    Mar 21, 2019 at 2:04
  • see my answer for details. the TL;DR is that the panel will let you backfeed a branch breaker, turning it into a main Mar 21, 2019 at 2:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.