Attach multiple grounds for smart switches in crowded 3-gang switch box

electricalgroundlightingsmart-switchwiring

I’ve recently upgraded a three-gang light switch box with three Kasa smart lights (a dimmer, three way light, and single pole switch).

I’ve been able to successfully install all three and they’re functioning, but I had to leave the box without connected ground wires (the “dumb” versions of the switches previously in the box were also ungrounded) until I can come up with a solution for my box.

My circuit is 20 amps and uses 12 AWG wires. The PVC switch box is a bit crowded now with the new smart switches. When it comes to neutrals and grounds, it contains:

  • Four neutrals bundled together (now seven total with the three smart light neutrals connected with the bundled four using a large twist nut cap, rated for up to 2 6 AWGs, min 3 12 — I figured it may work).
  • Four ground bare coppers bundled together with a crimp.

I’m trying to figure out how best to tie in the three green ground wires from the smart switches. I tried connecting with a screw cap like I did with the neutrals with no success. The bundled bare wires are much more stiff, and lengthwise the ends can barely be pulled beyond the threshold of the front of the box. Behind that there isn’t much room, especially for another large screw cap, because of the neutral bundle and cap as well as other hot, traveler wires, etc.

Is there some other solution I might try? Some combination of pigtailing? I know I can run everything without the ground connecting and the prior switches ran fine for 35 years without it, but would still like to figure out a way if I can.

Thanks in advance!

PICS: so I took pics during and afterward but not for this specific question, so I know they’re not ideal.

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First photo is of prior to taking out the old switches, you can clearly see the four bundled and capped neutrals and bundle of bare copper (paint splatter on it).

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Second pic: three (one switch is hidden — sorry again!) newly installed switches, if you zoom in behind you can see the large blue nut cap on the neutral bundle. The next step here was to tie the three ground wires from each light switch to the bundled bare copper ground, which for the reasons above, I was unsuccessful doing.

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Third picture, I didn’t have any better pics, so I included what it looks like on the wall just because it’s the little things. 🙂

Best Answer

  1. Remove the crimp. Just cut the wires below the crimp.
  2. Clean off the paint from the ends of the wires. A gentle scrape with finger nail or a wire stripper should work.
  3. Add a pigtail to each switch's ground terminal. Make sure they are long enough to reach across the box.
  4. I can't see from your photos if these switches have a ground terminal or just an integral green wire. If necessary, you can use additional wire nuts to splice the grounding pigtails.
  5. Add an appropriate wire nut to the new bundle of 6 ground wires. If your red and orange wire nuts are too small, it is okay to have 2 bundles of 4 wires including a pigtail between them rather than one big bundle of 6 wires.

I know I can run everything without the ground connecting

If you are subject to NEC rules, this violates Articles 110.3 and 404.9. From a practical perspective, if anything goes wrong with your ungrounded switches or wiring, then those metal screws holding up the face plate will be energized.

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