I just bought my first house and I want to replace this switch with

This smart switch.

The smart switch says it needs a ground wire, but when I opened the box up, it looks like there are only two wires here.

Is this box grounded? Would I need the ground wire?

See below for pictures:

enter image description here

enter image description here

enter image description here

  • 1
    I think you, or the instructions, are confusing the ground and the neutral, smart switches need a neutral. There does appears to be neutrals in the box, they are White, underneath that paint. You do also need a ground which is bare wire and in the box also. It should be attached to the green screw on the switch. – Alaska Man Dec 28 '20 at 22:51
  • @AlaskaMan, this is the switch I had in mind: amazon.com/Kasa-Smart-Light-Switch-TP-Link/dp/B01EZV35QU/… So that bundle on the left is neutral, and the bare copper on the right is ground? – J. Hoff Dec 28 '20 at 23:00
  • 1
    Yes i can see the grounds in a wire nut. The other wire nut may be neutrals but i can not tell from here. Jack has it right. – Alaska Man Dec 28 '20 at 23:05
  • 1
    @alaskaman there are some smart switches that require a grounding conductor. These are designed for systems with no neutral. I saw a top 10 web site no neutral but did not look to see if they were UL listed. GE was one of the mfg’s and I believe lutron also makes one – Ed Beal Dec 28 '20 at 23:28
  • @AlaskaMan Yeah, what Ed Beal says. UL gives a waiver for this: the products are designed so there is no failure mode that would ever leak more than a few milliamps of current onto the ground. Normally they leak <0.5ma to ground so several won't trip a GFCI. I thought I saw where NEC limits any given circuit to 8 smart switches, that would explain why. – Harper - Reinstate Monica Dec 29 '20 at 3:09

Your light switch is not grounded and neither is the plastic box. You do have a ground wire in the box. It's the bare copper wires wire nutted together. To ground a switch, you'd need to get a piece of 14 AWG wire and connect it to the group of bare copper wires and then to the switch. Most smart switches need a neutral, which isn't the same as a ground. The neutrals would be a group of white wires connected by a wire nut. Scrape some of the paint off the wires to make sure of the colors. Make sure the power's off before doing any work.

  • 1
    Correct, if the neutrals are present then you can pigtail to the switch just like the ground. Pigtail means adding a short piece of wire to the wire nut group and then that to the switch. – Alaska Man Dec 28 '20 at 23:08
  • 1
    Looking at the switch you linked to i see it has wires instead of terminal screws, so no pigtails are needed, just add the wires from the switch to the existing wire nuts. – Alaska Man Dec 28 '20 at 23:23
  • 1
    @AlaskaMan Thank you for that in depth definition of "pigtail". :-) – JACK Dec 29 '20 at 1:19
  • Thanks to you both! Good to know I can use the wires in the switch without getting additional wire for a pigtail! – J. Hoff Dec 29 '20 at 2:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.