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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:

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    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
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    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
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    @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
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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.

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    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
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    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
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    @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

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