Flipped breaker...House built in 50s

Pulled the old dimmer and there is only a hot (black wire) and a un-hot (white wire), but no bare copper ground. For new dimmer, do I just wire hot to black screw and un-hot wire to brass screw? (Lutron Maestro)

The new switch comes with a green ground wire...do I just shove it in the box and ignore?

Sometimes the box itself is grounded - do you see a ground going to the metal box?

agdoc2001 said:

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Sometimes the box itself is grounded - do you see a ground going to the metal box?

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https://imgur.com/a/70z8GX3

This is what I am looking at. Metal box, with small screw in back. Should I hook green wire from new switch to that screw in back of box?

Mid 50s construction likely doesn't have a ground run for lighting circuits. Highly unlikely the box is grounded (all I see is NM sheathed cable with no ground present. If you're talking about the same kind of Maestro dimmer I've seen, the ground lead is soldered on to the mounting bracket. I'd break it off entirely instead of having it float around freely inside the j-box.

Correct it is soldered onto the switch.

Any harm in it being connected to the back ground screw in the box even if the box is not grounded? (I already wired everything up... just waiting for a reply). Will break off if you think so otherwise.

No harm in having it connected to the screw. On the outside chance that the box is grounded, you've already got a ground path via the metal mounting bracket and top/bottom screws. The only thing I would advise against is leaving the ground wire unconnected in the box.

Thank you.

Nvm... answered my own question. Plugged an LED in there and it powered down completely.
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The fun continues... flipped the breaker and even when I power down the dimmer switch the light bulb stays on...

Possible the switch is rated for a LED bulb?

AnyOtherName said:

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Flipped breaker...House built in 50s

Pulled the old dimmer and there is only a hot (black wire) and a un-hot (white wire), but no bare copper ground. For new dimmer, do I just wire hot to black screw and un-hot wire to brass screw? (Lutron Maestro)

The new switch comes with a green ground wire...do I just shove it in the box and ignore?

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I realize it's working, but just to correct, in your situation, the white wire isn't a neutral. You have a switch loop. Both the white and black wires are hot. Typically the white wire will have marker or electrical tape on it indicating it's a hot lead. Usually, the hot will come down from the ceiling box on the white wire, and travel back in the black.

Just be aware if you ever replace the light fixture. You'll have the hot white and a white neutral in the ceiling box.

What this guy said is correct. You have a switch leg, not a hot and neutral.

In order to make your dimmer switch work correctly, you will have to rewire everything completely. Right now only the hot leg is coming down to the switch and getting interrupted. You need to add another run of wires so that both power and neutral come down to the switch, get interrupted, and then go back up to the fixture.

To add to the above, the reason why most dimmer switches need a neutral wire is because of how they accomplish the dimming feature. Rather than send full voltage downstream to the hot leg/fixture, they shed some of the voltage off the hot straight to the neutral. That decreases the voltage going to the light, and thus dims it down. Moving the dimmer up and down just modulates how much voltage is transferred between the downstream hot and neutral.

TheMoreYouKnow.jpg

Now that is a great explanation. Blue star for you.