Ground wire for light switch?
i am replacing light switches. the ground that comes from the wall should this be attached to the green ground screw on the light switch or directly to the box?
- Anonymous9 years agoFavorite Answer
If the box is metal the ground should already be looped around a green ground screw on the box. If not you should go ahead and do it. If the box is plastic, just attach the ground to the green screw on the switch.
- MarieLv 44 years ago
Except for the change in light control, I would say this was a dimmer switch wiring or wiring for a ceiling fan for the main room, but it has to be that they were going to put a double switch there when they were wiring but changed their minds when they were installing the switch boxes. It could also be a remodeling issue if the closet was added later. You should try capping two of the non-ground wires together and wire the switch with the ground and the remaining wire. Number each wire with a masking tape tage before you start and rotate which wire is hooked up how - it could take three tries to get the right wires hooked up. If the extra wires were not connected to each other initially, you can try just capping each of them, but the ceiling light may not work then and the entire thing may not work then, depending on the circuit.
- Jacob WLv 79 years ago
Mike is right. If the box is metal the ground from the cable must go to the box and a pigtail from the box to the ground on the switch. If it is a plastic box, the ground goes directly to the switch.
Someone asked why you need a ground on a switch. The answer is to make sure if the hot wire is compromised and touches anything but the hot screw on the switch it will blow the fuse or circuit breaker. Without a ground, the hot wire could energize the box or the switch and you will provide the ground when you touch it. Not good.
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- Lic. ElectricianLv 69 years ago
Thanks for the good answers Jacob and Mike.
One last item for clarity...
Never attach more than one wire per screw terminal. If all of your grounds are connected under a wirenut, but no means to connect to the switch (this used to be quite common before all switches were required to be grounded), then you need to put on a 'pigtail'. A 'pigtail' is simply a short piece of wire (in this case bare or green, because it is a ground) that is connected under the same wirenut and left hanging out to connect to your device.Source(s): NEC IBEW 191
- Frank KLv 49 years ago
Should be grounded to both a metal box and switch. If there is no place to screw-attach the wire to a metal box, you can remove the clips that keep the two screws(that attaches the switch to the box). This allows the switch contact with the box. There are also metal clips that are made to ground the wire to the box.
- 9 years ago
Why do you have to ground a light switch?
- captbob552Lv 49 years ago
The green screw. Attaching it to the box that the switch sits is does nothing.
- Anonymous9 years ago