Older Wiring - first time poster

Old 02-05-04, 10:17 PM
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Older Wiring - first time poster

I bought my first house 8 weeks ago and have begun remodelling. As far as electrical goes I've only changed some outlets, and had an electrical guy (not licensed) re-wire the bathroom as it is to studs.

The outlets were easy no surprises, one white wire and one black.

Tonight I am trying to change a switch. The switch is NOT a 3way, it only controls a light and there is no other switch controlling the light. When I took the switch apart I find a red wire and two black. In working further I find the black wire is one continuous line that has been cut and nutted back together with the switch hitting the line where the insulation has been removed and wrapped around one of the two screws (left side) while the red wire is screwed to the other side.

The new switch is a dimmer and has only 2 connectors and a ground wire, which will not be used as the circuit is not grounded.

I tried the dimmer (not smart) by reconnecting the fuse while the wires are exposed, just touching the red wire and the black wire with the 2 connectors coming from the dimmer. It works as it should but I remain confused.

Why do I have a red wire? And if I hook it up as tested will I damage anything? What is the right way?

Also, is it worth putting a dimmer in as the light itself starts buzzing when dimmed? Is there a light unit I can use that will not buzz? I will be replacing the light unit anyway.

Apologies for long post. Any help here would be much appreciated.
Old 02-05-04, 10:42 PM
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Sounds like the one of the black wires is a hot feed. It feeds the switch, plus probably goes on to another receptacle. The red is the switched wire and that goes to the light fixture.

Some bulb will buzz when you connect them to a dimmer and lower the light output. Try a better quality bulb or a rough service or 130 volt bulb. They usually have a stronger filament which is supported better and will probably produce less noise.

What type of wiring do you have? Is this non-metallic cables or conduit? Since your dimmer has wire leads on it, rather than screws, you'll need to cut off the top portion of the wire, past the uninsulated section, so you can put the the 2 house black wires, along with the dimmer lead into a wire nut.
Old 02-07-04, 07:40 AM
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I wired it up, nutting one dimmer switch wire with the two black and the other dimmer switch wire to the red and seems you were right about the configuraton. Thank you.

I have not purchased the new light fixture yet, but will take your advice into consideration when purchasing the bulb.

I have non-metalic wiring.

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