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Sub panel double wired circuits and grounds and neutrals sharing the same bus bar, is it OK to wire like this? Sorry I am not a professional in this field. 2 red and 2 black coming from main panel.

  • Does this panel have spare spaces in it? – ThreePhaseEel Apr 16 at 23:10
  • No.The cover has exactly cut outs so only breakers are visible. – user99576 Apr 17 at 17:36
  • That isn't the metric of "spare spaces" -- are there places on the cover that look like they could be twisted out? – ThreePhaseEel Apr 17 at 22:37
  • Nope, there are no such places. – user99576 Apr 23 at 12:33
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No on several counts.

This looks like a subpanel. Neutral bars and ground bars must be rigidly separated in subpanels. Period. If there is groundless feeder coming to it, you still need to separate neutrals and grounds for that happy day when you retrofit ground, which is legal anytime. (well, since 2014 for almost all circuits).


Note how the main lugs are double-tapped. You cannot do that unless the lugs or the equipment they come with says in the labeling or instructions that you can do that. Because the UL listing depends on following the instructions.

To fix that, see if the lugs are replaceable. If they are, see if they can be changed to duplex lugs (lugs with 2 voids). If they can't, then get a 3-hole Polaris connector and a short pigtail for each hot.

Often the small holes in the neutral or ground bar can accept up to a #6, and often those bars have some holes intended for larger wires. Using those is fine.

Another way to avoid double-tapping on that panel is to move one pair of wires over to a circuit breaker of appropriate size. That's a $10 solution. This can double as a subpanel breaker (if needed) or outbuilding shutoff switch (if needed). For what it's worth, they do make double-stuff breakers in CH.


Speaking of that, you cannot double-tap the neutral bar (2 neutrals on one lug) again unless the labeling or instructions say you can.

Ditto ditto grounds, though I have heard of panels saying you can up to triple-tap a ground lug.

  • I would like to get some clarification. Sorry again I am not a professional, just trying to get common sense out of it. Two red wires coming from Main panel as well as two black ones. My logic tells me that 2 feeding wires are better than one because it can deliver more then one. Just like 2 hose of the same diameter filling up the pool faster than one. So there is less chance of fire because load on each is less. Tell me where am I wrong? Thank you. – user99576 Apr 17 at 17:25
  • @user99576 the problem is that the lug (connector) on the loadcenter has not been tested/rated for having two different wires shoved into it, so we don't know if it's made a good connection to those wires, or if it's making a good connection to one and a bad connection to the other, or if they are both connected poorly – ThreePhaseEel Apr 23 at 23:55
  • And that other thing you're talking about, paralleling, is super bad. The wires don't back each other up, they greatly increase risk. A wire break is a common thing, it shouldn't burn down your house. But if one wire breaks, the other one overheats! If you fix that by downsizing the breaker to an appropriate size for 1 wire, there's no reason to have 2 wires. – Harper - Reinstate Monica Apr 24 at 2:20
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Generally no, unless the lugs are listed to hold two wires (most are not). You can check the panel labeling to see if they are, but if it does not mention it then it is not okay.

Separate from whether the lugs can handle two wires is the question of how those wires are being used. If they're paralleled wires from the same source, that is not allowed (paralleling is only allowed on very large conductor sizes; these are far too small). If one is from the source and the other is a feed-through to a second panel this may be okay, but you'd have to check the feeder tap rules to make sure.

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