Attached are the photos of my outside “main” panel and the sub-panel inside my garage. 

The panel outside in backyard (main) does not have a standalone breaker “main” breaker. It is inline with the other 5 breakers on that panel - which feed-


Inside my garage on the other side of the house is the sub-panel that distributes the power from the outside “main” to the rest of the house, excluding the Air conditioners and stove which are on the outside “main” panel pictured above. 

Now, my goal WAS to hookup a power inlet box for a generator to the outside “main” breaker box with a proper interlock kit, so that the main breaker could never be on when the generator breaker is on. Hence the name “interlock kit”. This is the only legal and cost effective way to hookup a generator to house panel.

The above mentioned strategy will NOT work because the main breaker is INLINE with the other breakers. CANNOT INSTALL INTERLOCK KIT PER LARGEST LOCAL ELECTRICIAN IN MY AREA.

The next picture below ⬇️ is of the sub-panel in the garage. I noticed that there is a “knockout” at the top of the panel that would appear (I’m not an electrician) to allow for a Main breaker to be installed, which would allow for an “interlock kit” to also be installed, therefore allowing me to run my inlet box without any concern regarding safety or legality. Please correct me if I’m wrong.  See pictures below ⬇️ 

Also, am I able to circumvent all of this headache by just installing a 100amp or 200amp manual 3 Pole disconnect into the outside MAIN panel? Then run my 50amp generator inlet box to the disconnect?

Please help, hurricane season is upon us.


  • Who do you have for an electric utility, and what loads do you want to power from your generator? Commented Jun 19, 2021 at 15:59
  • Also, what do you have for a generator even, or are you still shopping for one? Commented Jun 19, 2021 at 16:23
  • RE: "installing a 100amp or 200amp manual 3 Pole disconnect" , To just feed the interior panel you would need a DPDT switch to isolate supplies, typically sold as a transfer switch. A 100A transfer switch will often cost twice as building one using a small panel outside with breaker interlock to feed interior panel. If you can route generator feed to interior panel would confirm if main breaker kit is still available first. Commented Jun 19, 2021 at 16:44
  • FYI Your main panel is a "Rule of 6" type. Code allows (allowed?) a main panel without a main as long as you can turn everything off by turning off at most 6 breakers.
    – DoxyLover
    Commented Jun 19, 2021 at 18:39
  • I already purchased a Champion 11500 watt portable generator. Is it feasible for me to just install a main breaker in the sub panel in the garage that has the knockout in place for it? Is the assumption that if I have a main breaker in the garage, I can install an interlock kit and feed the 50amp generator inlet to a 50amp breaker in the panel? I would have to move all of B side down to accommodate the 50amp breaker. Is this a logical train of thought? I assure you I am nowhere near understanding the details of this but I need to make it happen. Any advice would be greatly appreciated. Commented Jun 19, 2021 at 20:37

1 Answer 1


I would remove the dead face on that main panel and see if you can install a main breaker (probably can) while the dead face is off see if there are 4 additional slots at the bottom where they are not currently knocked out. Main breaker + inter lock kit and indeed double pole all legal on your main (what I have installed) around 200$ in parts.

Your Answer

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

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