Federal Pacific 200a main panel problem with oversized 100a 2pole breaker

Question

There is a 200a FPE breaker box (yes, I am aware of all the problems). It is not in the homeowners budget to replace at this time. He has 2 issues:

1. His panel is full
2. His electric furnace is an older 100a furnace. The 100a breaker in the panel is a double pole but it also over crowds the adjoining spot on the right rail. So, essentially, his double 100a breaker is taking up 4 spots (2 on left rail and creeping over (preventing other breakers) and partially covering 2 spots on the right rail.

This is a problem because the home owner has to disconnect the 100a to plug in the 30a for the dryer. I advised him that is not ideal in any situation, but extra not ideal with a FPE panel.

I thought about installing a sub panel for him right next to the main panel and just re-route the dryer run to that one but I have not installed a sub panel before. I am competent in my ability to do so but would like to hear suggestions from others before I attempt that feat.

thanks!

Answer 1

The 100A breaker is overcrowding the other slots for a reason: to enforce stab limits. Even a stopped clock is right twice a day, and FPE got that right.

If you did what you wanted to, you would have 130A on those two stabs. That's over stab limits for a lot of modern panels! If you've ever seen panels where the main breaker is in the upper left corner and nothing is allowed across from it even though there's nothing wrong with those spaces, that is why.

So if you have felt righteous to do this because you feel you are working around a panel defect, no. This is a plain case of playing swap-the-breaker on an overfull and overloaded panel, with known stab-reliability issues, doing the very thing that has everyone spooked.

The 100A breaker is not double size. It is normal size 2-pole. The other breakers are double-stuff. This is a 12-space panel with 8 spaces double-stuffed. A 12-space panel on a 200A, all-electric house. One has to woder if this was permitted in the first place!

Kill it with fire before it kills you with fire

If you're family, stop fooling around and swap the main panel. It's not any harder than a subpanel, you just have to work in the dark because the meter is pulled. Shop smart for a 40-space of a sensible physical dimension (CH, QO) and combo-pack that includes some breakers. Don't even attempt to solve AFCI or GFCI issues, aluminum wiring issues (loop back on those later, just use Al-rated breakers) etc. If the AHJ insists on increasing project scope to include ancillary stuff like that, then just don't pull a permit and do it underground - but do it correctly. Do double-check your wire sizes - I see too many 30s and not enough 15s.

If you're a contractor, run... this panel is a fire-starter, and if one does, your insurer may decide you're on your own!

Why not a subpanel?

Because I don't believe it's a significant cost savings over just swapping the main panel, it's a band-aid on a very bad situation, and the heat needs the whole 100A, there isn't spare (electrical) space in the subpanel for anything.

Answer 2

It sounds like a sub panel is the way to go, in my opinion as well, in this particular case. I agree.

Any sub panel installed will have to have any connections made between the ground and the neutrals in that sub panel REMOVED... Reason being that if there are any ground faults that occur within the newly installed sub panel's branch circuits..., This way, any ground faults will travel only through the grounding system and not the neutral which goes back to your main panel.

I'm not sure if your intentions are to pull a homeowner's permit or something else to have it inspected, but that is entirely your call. I would.

Answer 3

Change out your service. Half the time they don't trip when needed (federal). Spend the money to keep it safe. Have a license electrician do the job right with arc faults and gfci breakers. Size your breakers to the wire size with the right grounding and bonding. Don't try it on your own. One screw up, your dead or the person living there is dead. Ever seen somebody electrocuted? It will haunt you for the rest of your life. Do the right thing.