I want to switch a GFI outlet. It will be on a single 20 Amp circuit breaker with no other outlets or devices in the circuit or downstream from the outlet. It will be used to switch a dust collection unit on and off in my workshop.

Is the proper way to wire this:

  • Place the switch in the hot wire going to the "line" side of the GFCI outlet.

  • Run the neutral wire uninterrupted to the "line" side of the GFCI outlet.

  • Connect ground wires as usual, switch and outlet.

2 Answers 2


Yes that is correct - you always want to switch the hot. Just make sure you use a switch and wire rated for 20amps.

  • Up-voted for concise answer.
    – dbracey
    Commented Sep 4, 2012 at 0:59
  • 1
    AFAICT, this would not provide any protection at the switch (e.g. if somehow the switch screw came into contact with the hot, there would be no protection against electrocution) Of course, the question didn't explicitly ask for that, but for the sake of completeness, I'm linking to this answer, which addresses how to protect the switch too diy.stackexchange.com/a/28625/11812
    – tom
    Commented Nov 30, 2015 at 18:28

If power is going to the switch first, you'll place the hot conductor on one screw of the switch, with the conductor on the other screw going to the hot (generally copper colored) screw of the GFCI on the line side. The neutrals in the switch box will be wire nutted together, with the neutral conductor leading to the receptacle box going to the silver screw on the line side. Grounding is still done as common. If power is going to the receptacle box first, you'll have to run a switch-leg. In this case, the neutral entering the receptacle box will be placed on the silver screw on the line side, but the hot will be wire nutted to a new piece of Romex. Personally, I nut the black (hot) conductor to the white that heads up to the switch (of course, you tape the white conductor over with black electrical tape on both ends). Both the white and black in the switch box are landed on the screws of the switch, and back in the receptacle box, the black lands on the hot screw (generally copper colored) on the line side. Grounding is still done as common, don't forget to connect the ground in the switch leg so you can ground your switch box, too. Have you used a switched GFCI before? In my experience, it's a common problem in bathrooms that a GFCI is tripped when a light (which is on the protected, or load, side of the GFCI) is turned on. You may find that he GFCI trips out when you fire up your dust collection unit sometimes. All you have to do in this instance is to hit the "reset" button, but it can be an annoyance.

  • Thanks for the answers. I saw a post elsewhere about this that made no sense to me. I'll carry on. Again, thank you.
    – Ralph
    Commented Sep 4, 2012 at 1:10

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