grounding switch?

Jeremy Hillary Boob, PhD

I'm in the process of replacing the light switches throughout my house (the old ones have been painted over and many of them don't function smoothly). I bought "heavy duty grounding switches" because I like the way they feel, not because they are "heavy duty grounding switches". The switches I'm replacing are not "grounding switches", that is, they do not connect to a ground wire. Is it
a) necessary,
b) a good idea, or
c) totally pointless
for me to connect a ground wire to each of these new switches? So far, I've come across one switch where there is no ground wire at the switch, so if the answer is a) or b), what would I do in that case? Thanks.

Gigs

If it's there, you are supposed to use it. If the wire is completely missing I believe you are allowed to replace the switch and leave it ungrounded though. Metal box should be bonded if it's metal of course.

It's a pretty minor safety issue, but the switch becoming energized could energize the screws and/or the plate if the plate's metallic.

Yoyizit

I think it possible that no one has died in the US for this reason in 1, 5, 10 or more years. If you try to get data on this specific cause of death you will probably get the runaround even though your tax dollars paid for collecting these kind of data.

Some of the reasons for this is the (realistic and rational) fear that people have of electricity.

The switch would have to have failed by shorting to the frame and not alert you by failing to function or by a different "feel."
The switch manu has data on how many failures of this type occur. But I don't think even a lawyer could pry this info out of them.

Also, you'd have to touch a mounting screw of the failed switch and be grounded at the same time. To be really injured your hands would have to be wet or sweaty. Given the total area of the switch mounting plate, handle, etc., how likely is it that anyone would ever touch the mounting screws? Who ever messes with electrical things with wet hands?

The switch height above ground is probably set so that if a kid is tall enough to touch the switch he/she probably has good judgement regarding the danger of electricity.

And aren't the screw heads painted?

J. V.

If you like them use them. Not required.

Wildie

Reminds me of a time when I was employed by a large institution!
All the new lighting used 347 volts.
Naturally, 347 volt rated switches were required.
A painter removed the covers in a room that he was painting!
Inadvertantly, one of the cover screws that he was holding, fell from his hand and into the switch box.
Unconcerned, he attempted to retrieve it with his finger.
Needless to say, he was unsuccessful and had a burned finger to boot!
I doubt that a grounded switch frame would have helped!

Stubbie

The replacement of a switch in a box where an equipment grounding conductor is not provided is allowed by the electrical codes. However, you may not use a metal faceplate or you must provide the circuit with gfci protection. NEC 404.9 (B) exception.

Let me give an example for this requirement. I'm in the kitchen cooking on my range. There is a double gang switch box on the wall next to my range. The circuit providing power to that switch box does not contain an equipment ground. The box has a metal faceplate. That metal faceplate has become energized at line voltage due to a fault to the metal box with the hot wire. I have my hand on the metal range and touch the metal switch plate as I turn the kitchen light off with my other hand. There is a very good chance I may be electrocuted. The metal frame of the range is bonded to ground or neutral depending on 3 wire or 4 wire connection. I will have just about as good of a complete circuit back to the source transformer through my heart as I could possibly imagine.

Jeremy Hillary Boob, PhD

This is interesting. I also bought metal faceplates (my wife thinks they look nicer and will be easier to keep clean). So, it sounds like the regulation you quoted says that all of the circuits where these metal faceplates reside must have GFCI protection. Is that correct?

Stubbie

That is correct. The gfci will not protect you necessarily from a shock but it will deenergize the circuit fast to enough to keep you safe.

Gigs

I believe if you have proper ground bonding you do not need a GFCI even with the metal faceplate switches.

Just make sure that the ground wire is hooked to the switch and also to the box if the box is metal.

On the switch boxes where you are missing a ground wire you should ensure there is GFCI protection upstream though. You can use a GFCI breaker on the whole circuit for ease of installation, if you'd like. I'm sure you can afford it on your PhD's salary.

Jeremy Hillary Boob, PhD

So which is it? Also, what about metal faceplates on outlets? Thanks.

Stubbie

If you do not have a grounding means.. ie... an equipment ground wire included in the wiring means you follow the exceptions previously mentioned. No ground wire no metal faceplate... if you install a metal face plate then gfci must be provided.

Otherwise you must use non-conductive face plates.

If an equipment ground is provided in the wiring means then you must connect the egc to the switch yoke regardless whether the box is metal or not.

Jeremy Hillary Boob, PhD

Sorry if I'm being dense here, but I just want to make sure I've got this correct. Here's the way I understand it...

1) If there is a ground wire at the switch, I must use it to ground the switch. It is then OK to use a metal faceplate.
2) If there is no ground wire at the switch, I cannot use a metal faceplate, unless the circuit if GFCI protected.

Is that right?

jamiedolan

YES to 1 and 2. And if the box is metal, the ground wire must also be connected to the box.
Jamie

Rdhodson

Like the original poster, I replaced a light switch (with a dimmer) and there was no ground wire. This switch is in my bathroom, and it is on the same circuit with the GFCI electrical outlet (when I push the test button on the outlet, the light with the new switch turns off, too).

Is it ok to leave this switch ungrounded, since the GFCI is on the same circuit?

I appreciate any help or advice!

MisterZ

The circuit is gfi protected. I believe you are a-ok

However, if the switch box is metal it should be grounded to the switch

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