I recently posted a question about my panel, Cutler Hammer CH30E, being properly grounded. All ground wires were twisted together and stuck in two lugs screwed into the left side of the panel. enter image description here

This didn't go over well with Harper. So I got the appropriate grounding bar for the panel. The two pretapped holes for the bar are about 3/4" above the lug /breaker insert and another set 3/4" below the insert. The lower location would be great except none of the grounds will reach. The top location would be behind the 2-2/0 Al wires. It would fit but be close.

Are the panels designed so that the lug/breaker insert can be rotated 180 degrees and the feed come in from the bottom instead of the top. This would free up the top area for the bar and all the ground wires would reach.

There are some improper handle ties from when they built the house. I've got correct ones on order.

UPDATE: Well I think I corrected the problem. I removed the two lugs holding all the ground wire. shown below are the two lugs and the screws that held them to the side of the box. enter image description here

Here's the panel with the new grounding bar installed. The rep at the electrical supply store ( not Home Depot) assured me I could double ground on the holes, even triple ground, since I got the suggested grounding bar for the cutler Hammer panel. I tried to clean the panel up a bit but was limited because the builders cut the wires so short.

enter image description here

Thanks for your help.

  • Do you mean that none of the grounds will reach the new location, not none of the neutrals? Jan 29, 2020 at 0:15
  • @ThreePhaseEel My bad. None of the grounds...
    – JACK
    Jan 29, 2020 at 0:22
  • (Post-update) Just loving that big fat green bonding wire. Feb 1, 2020 at 5:18
  • @A.I.Breveleri I didn't trust those two 8-32's
    – JACK
    Feb 1, 2020 at 12:24

2 Answers 2


That right there is what a panel should look like. Note the empty void for a third service wire; that's for 3-phase which means it's industrial grade. The breakers are 3/4" wide; this would only fit 20 breakers if they were 1" tall. It's very, very busy in there, but only because all the wires come in the top hole. It's not anything to worry about. They did you the disfavor of runting off all the wires so they barely reach the breaker/bar, which frustrates moving anything around or adding AFCIs/GFCIs. But here's the thing:

Ground bars do not need to be in the factory anointed locations

They can be placed anywhere in the panel. except the screws can't mount on a knockout (it can bridge across an unused knockout). But you need to very carefully drill and tap the mounting holes yourself, -32 pitch or finer, typically an 8-32 or 10-32 or 1/4-28 screw (whatever they provide in the kit). The holes must be the right size, which means looking it up on the web and hitting a hardware store for the correct bit, probably a numbered bit like #27. I would wrap the drill bit with masking tape so only the first 3/16" is exposed, so it can't nick a wire.

If you strip out a hole, just move the bar over 1/4" and try again.

Mind you, the -32 requirement is for electrical contact. I wouldn't rely on it for electrical contact. I'd use a nice fat ground wire also, going from the ground lug you're abandoning through your first bar, through your second, pop up a little for the clamp meter, and then onward to the neutral bar.

As far as flipping the bus bar assembly

It looks to me like Cutler Hammer went to a fair amount of work specifically to make the bus bar assembly flippable. But that appears to be so they could do it at the factory, because there's a problem.

The cover won't line up. You could contact Eaton and see if they can supply a cover for that; it's possible.

  • I agree with @harper on the answer and for the comments, although main at bottom is legal for a sideways on off , I think it looks cheap as someone saved 25$ what other corners did they cut? At my current plant the old owner cut lots of corners many were not legal but inspectors did not catch. I have changed many things to code compliant our downtime for failed wiring has gone down significantly , still finding splices in the pipe on feeders, usually because of a failure.
    – Ed Beal
    Jan 28, 2020 at 23:55
  • You may need to drill/tap a 1/4-28 hole instead of a 10-32, depending on the ground bar you have. (I know the Penn-Union NA-400 series bars mount using 1/4-28 holes and screws, as per a convo I had with their support folks; it would not surprise me if that was typical behavior for LC ground bars.) Jan 29, 2020 at 0:16
  • 1
    @ThreePhaseEel the C.H. ground bar came wit 8-32 screws so that's what I drilled at tapped. See updated photos.
    – JACK
    Feb 1, 2020 at 0:52
  • @EdBeal I really don't know why they did this with the grounding. I've never had any problems in 39 years. Only because of this site that i checked it out. Thanks.
    – JACK
    Feb 1, 2020 at 0:58
  • @Harper Good advise on moving the ground bar to another location. Thanks. The new bar turned out pretty good.
    – JACK
    Feb 1, 2020 at 22:43

If you rotate it, the obvious constraint is that the breakers still have to line up with the aperture in the front panel. At first glance, it looks like the breakers are not symmetrical with the mounting screw pattern, and even if they were, if you did swap the rail around it'd leave very little room for manipulating the feed wires into the lugs - they don't form into nice tight radii.

Many boxes can be used upside down for bottom feeds, so if there's symmetrical mountings in the back plate for everything (and things like the door latch work the other way up) you can invert both the rail and the front plate, to leave the larger space at the bottom.

  • To be utterly clear, you'll not be "inverting the rail" without also "inverting the box it's mounted to" - I personally have an "upside down" panel, which is, of course, listed for use that way, but I had to talk my electrician out of the mindset that the main should be at the top, even though the feed is from the bottom.
    – Ecnerwal
    Jan 28, 2020 at 22:55
  • @Ecnerwal It merely offends my sense of user-interface design when a main breaker is not obvious. So I'd cheerfully flip a panel that had a bigger, obvious, different main breaker; but on a backfed type where the main looks like just another breaker, I'd strongly prefer that be on top. Jan 28, 2020 at 22:58
  • QO40 - blatantly different, 4X the size of a regular breaker.
    – Ecnerwal
    Jan 28, 2020 at 22:59

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