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Ground - New switch old wiring

I replaced a switch in th bathroom of my 100 year old house and the wiring is insulated with, I believe cloth, I guess the typical old type of wiring. Anyway, the switch that I replaced did not have a ground wire and the new one does. Should I ground it to the box, even though I am not sure if the box itself if grounded? If not, should I put the old switch back in?

NEC
Re: Ground - New switch old wiring

The box is not grounded. It is fine to put the new switch in and not tie the ground to anything.

Re: Ground - New switch old wiring
NEC wrote:

The box is not grounded. It is fine to put the new switch in and not tie the ground to anything.

??

I dont disagree with NEC but I think he also wanted to say that you have to make sure the fixture is rated for use with no Equipment ground, usually meaning no exposed metal parts.

I will add that no equipment ground is a pretty good indication that the wiring in your home is suspect to say the least and looking into it a little further would probably be a good idea.

NEC
Re: Ground - New switch old wiring

I think Lloyd may have been thinking about NEC article 404.9(B)

"Exception to (B): Where no means exists within the snapswitch
enclosure for connecting to the equipment grounding
conductor or where the wiring method does not include
or provide an equipment grounding conductor, a snap
switch without a connection to an equipment grounding
conductor shall be permitted for replacement purposes
only. A snap switch wired under the provisions of this exception
and located within reach of earth, grade, conducting
floors, or other conducting surfaces shall be provided
with a faceplate of nonconducting, noncombustible material
or shall be protected by a ground-fault circuit
interrupter."

Note that the exception includes, "located within reach of earth, grade, conducting floors,or other conducting surfaces." and then the face plate or GFCI requirements if located therein. Notice also that if the switch is not located in an area mentioned above you can just replace it and are good to go.

Re: Ground - New switch old wiring
NEC wrote:

I think Lloyd may have been thinking about NEC article 404.9(B)

"Exception to (B): Where no means exists within the snapswitch
enclosure for connecting to the equipment grounding
conductor or where the wiring method does not include
or provide an equipment grounding conductor, a snap
switch without a connection to an equipment grounding
conductor shall be permitted for replacement purposes
only. A snap switch wired under the provisions of this exception
and located within reach of earth, grade, conducting
floors, or other conducting surfaces shall be provided
with a faceplate of nonconducting, noncombustible material
or shall be protected by a ground-fault circuit
interrupter."

Note that the exception includes, "located within reach of earth, grade, conducting floors,or other conducting surfaces." and then the face plate or GFCI requirements if located therein. Notice also that if the switch is not located in an area mentioned above you can just replace it and are good to go.

I was refferring to the need to install a fixture rated for use without an equipment ground, ATM I dont have the article to reference however.
Your point is noted but I wonder what "within reach" means
48"CFF ? 54?

Lets step awy from the NEC for a second and look at the purpose...
To avoid having "unbonded" metal non current carrying parts being exposed. Put a plastic cover on the switch your probably ok, but installing a fixture with the same metals parts exposed and unbonded to an equipment ground would create the same potential hazzard 404.9 tries to avoid the plastic cover requirements. In fact theres probably more likely a chance for a short in a chandelier then a switch, hence more of a need to ground the metal parts.

So, I think I'm agreeing just think its common to underestimate the importance of grounding fixtures.

Example .. short in a fixture wire no egc .. bulb doesnt come on so homeowner goes to change it grabs the fixture... becomes the equipment ground... etc etc

NEC
Re: Ground - New switch old wiring
Lloyd wrote:

I was refferring to the need to install a fixture rated for use without an equipment ground, ATM I dont have the article to reference however.
Your point is noted but I wonder what "within reach" means
48"CFF ? 54?

Lets step awy from the NEC for a second and look at the purpose...
To avoid having "unbonded" metal non current carrying parts being exposed. Put a plastic cover on the switch your probably ok, but installing a fixture with the same metals parts exposed and unbonded to an equipment ground would create the same potential hazzard 404.9 tries to avoid the plastic cover requirements. In fact theres probably more likely a chance for a short in a chandelier then a switch, hence more of a need to ground the metal parts.

So, I think I'm agreeing just think its common to underestimate the importance of grounding fixtures.

Example .. short in a fixture wire no egc .. bulb doesnt come on so homeowner goes to change it grabs the fixture... becomes the equipment ground... etc etc

"Jhust make shurr youh useh a fibba glass shtep ladda, Thape tha hends of the whias and ahll will be fhine." :D

Spoken with an Alan G. Accent............:D

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