(Questions in bold at the bottom)

I recently purchased a Siemens E0816ML1125S load center for use as a subpanel in my basement:

enter image description here

I installed a ground bus bar, located horizontally under where the breakers snap in.

As I began wiring it, I realized that most breaker boxes I've seen have two bus bars with a crossover shunt between the two neutrals (in addition to a ground bar). But the Siemens box doesn't have a mounting location for the second neutral bus bar.

So one option would be to mount a second bus bar on the left side, using some sort of plastic standoffs (it being a subpanel, I want to isolate neutral and the grounded box here). But is it acceptable/common to just use the terminals on the right side neutral bus, even for circuits whose breaker will be on the left?

Is the eventual messy wiring acceptable?


  • Ground bar in horizontal position is a good idea. What level of NEC does you AHJ say you have to meet for the new panels and the circuits it covers? How many circuits and what amperage is the sub panel going to handle? The Single Neutral Bar of the right side is probably fine unless your AFCI/GFCI Neutral pigtails are not long enough. You can still run the wiring pretty neatly with the one Neutral bar! Aug 1, 2018 at 2:35
  • Is the plastic strip that the neutral bar is on part of the plastic strip to its left or is it a separate piece which is clamped to the box by the screw? Could you get another neutral bar with its insulating support and install it on the left? Aug 1, 2018 at 2:42
  • @JimStewart Yes, it is. It's not a separate piece that I could purchase another one of. If I found one with plastic standoffs (or just bought another bar and plastic standoffs), I could probably mount it to the panel with nylon screws.
    – jedwards
    Aug 1, 2018 at 2:51
  • @LimoDRIVER 2008 NEC (2014 adoption in progress). 5 circuits, with a 15A breaker on each, but was planning on running a 125A breaker-backed feeder to it for any future expansion. I'll be sure to be as neat as possible if I go with the single bar. Thanks!
    – jedwards
    Aug 1, 2018 at 2:57
  • Can you purchase a neutral bar assembly with plastic support and mount it on the left side rotated 180 deg (head down)? Aug 1, 2018 at 3:07

2 Answers 2


The reason you only have one neutral busbar is that your panel is super, super, super small and there simply aren't enough circuits to need 2 neutral bars. Larger panels don't have 2 neutral bars for neatness, they have 2 bars to provide enough neutral/ground screws (if main panel). You shouldn't even worry about terminating the neutral on the same side of the breaker. One thing we preach a lot here is "don't save money on the panel - you'll only regret it later".

For instance, with 8 spaces, and if you totally fill it with 15A breakers, that will only be 60A (remembering the feed is 240V). Running 125A feeder to it is a complete waste of your money -- or to be more precise, this postage-stamp panel is a complete waste of your time. I would return it to the store and spend a little extra on something like a 24-space. You'll thank us later!

As far as neatness, there is no Code requirement for neatness, at least, not in the way you're about to see. What you actually need is enough slack on your hot wires so you can move breakers around without limitation, and enough on your neutrals so you can bring them to the breaker on the happy day you upgrade to AFCI or GFCI.

Grounds need only be long enough to reach the ground bar; they'll never move.

And that should be reasonably tidy; it doesn't need to be Mom's spaghetti. What the 110.12 neatness rule is saying is don't just toss it all in higgledy piggledy so it looks like a grenade went off in there. Try to comb it a little.

Here's what you don't need: this guy has painted himself into a corner.

enter image description here

I feel pretty / Oh, so pretty / I feel pretty, and witty, and carefree....

Whatever brain cells this guy used to style the panel, he should've used to do a better job of the actual work. For instance where's the well marked white tape on the neutral wire? That's not optional. What is optional is different color hots; better to make them both black (since they are interchangeable) and the neutral red (since it is not) and taped too. How does this "pro" not own white tape?

Look at the grounds on the neutral bar. Sloppy. This guy does main panels all daaaaaaay... and it's allowed in main panels, but sloppy and a bad habit. If neatness matters, why not use panels with ground bars, and tuck them directly out of the way first? If this panel were ever made a subpanel, a bunch of ugly wirenut extensions would be needed.

He's cut all his neutrals an inch or two too short, so he'll be either angling or wire-nutting every neutral when he goes to add AFCI/GFCI.

But those top circuits can never be moved to any other position. He's murdered all the slack. So if he needs to move things around to make them more logical, or rearrange to fit a 2-pole breaker somewhere, or he needs to use double-stuff breakers and those only fit in the bottom 8 spaces... he's cut off his nose to spite his face. Why do that? Slack is cheap.

  • I agree with most everything but NEC 110.12 requires work to be done in a neat and workmanship like manor, that has been in code for as long as I can remember. Some inspectors are total azzes on this and won't all small service loops that I put in in case breakers need to be moved to balance loads.
    – Ed Beal
    Aug 1, 2018 at 20:21

This is fine

It is normal and acceptable for a small loadcenter like this to only have a single neutral busbar. Simply bundle the neutrals from the left side across the top rear or bottom rear gutter space to route them to the right.

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