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Trouble with Electric Circut Answered

I am trying to make a proofing box for bread making, and have run into a small snag. When I try to adjust the electricity going to the light bulbs in the box with my dimmer switch nothing happens, also when I try to turn the light bulbs off with the rheostat it trips my circuit breaker. I am using 4 7watt 120volt bulbs arranger in a parallel circuit, which are connected to a 600watt dimmer switch. If anyone knows what I am doing wrong I would appreciate the help.


. The switch/dimmer goes in series with the load, not parallel.

. And the lamps need to be in parallel. Confusing, huh? . OK, connect the hot wire from the wall to one side of the dimmer. Connect the other side of the dimmer to one leg of each lamp. Connect the other legs of the lamps to the neutral from the wall.

Okay, I did what you said and it has stopped tripping the breaker. However, I still cannot dim the lights. Any ideas?

. You have a 28W load on a 600W dimmer. Add more lights (150-200W ought to be enough). If that doesn't work, I suspect you've blown the dimmer. Or get a dimmer rated for fewer watts

Can you recomend a dimmer switch I should buy, or of a way to modify the one I already have?

does it work when you connect it to mains in series with high watt incandescent or halogen bulb ? if yes the load of 4 small lights is too small if no the dimmer is bad

. A quick search shows that 600W is the standard size for dimmers. . Any dimmer should "work." Even if the load is not great enough for the dimmer to function properly, you should still have some operation, even if it's pretty much on/off. If you are getting no reaction, I suspect the dimmer is bad. Try it with a 100W incandescent light bulb.

I just did a few tests with the dimmer, and it is definitely bad. Thanks for everyone’s help!

. It's been a while since I worked with dimmers. I can't remember if the dimmer needs to be wired with one particular side hot or not. If so, it should be marked on the dimmer somewhere or check the docs that came with it.

I check the docs on his dimmer, it doesn't seem to be polarized. My dinning room chandelier is 6X7watts and is connected to a 600 watt dimmer, so I don't think that's his problem. Jury rig another simple circuit, dimmer + 60watt light and make sure the dimmer is good.

> 6X7watts and is connected to a 600 watt dimmer . OK. I guess we can throw that theory out. . . Sounding more and more like a bad dimmer. Or wiring.

Hey Sedgewick, thank you, when I was trying to help you, I filled out a survey at the Lutron site, yesterday a complimentary sample of a Lutron eco-dim dimmer showed up on my doorstep. pretty sweet, that's a $25 dollar item.

As has been already noted, the dimmer switch can't be wired "in parallel", for the same reason you wouldn't wire an on / off switch that way....when the resistance of the dimmer approaches 0, you have a short (thus the breaker problem).

When you say nothing happens in the one scenario, do you mean the lights do not dim? If so, I can't see any way that the dimmer "shouldn't work unless it has it's own set of problems (bad/fried dimmer)

Yea, it is a mess of wires:).Here is a picture of the bulbs I am using. They are 7 watt filament bulbs and add up to 28 watts. Everything seems to work except the dimmer switch which is brand new.


Imput voltage = 120VAC
Light bulbs = 7watts 120VAC
Dimmer switch= 600watts 120VAC single pole


When everything's in parallel like this the dimmer will have no effect on the lights. But it will but trip the breaker, as you've seen... Follow uncle Nacho's advice...

It is hard to tell what is going on in that pic, it shouldn't much matter if the lights are in series of parallel, but the dimmer should be in series with the load.

I tried to place the dimmer switch in series with the load, but had the same trouble.

That looks like a mess of wires and I guess you are playing around with house current. I think usually dimmer switches are used on house lighting that are those 65watt reflector type bulbs. You can't use flourescents or CFL bulbs with a normal dimmer switch. The switch should be in your circuit attenuating and switching off the "hot" black wire. It looks weird on how it is wired up. It should be in series and not jumpering off of a wire in parallel or creating some other short. Make a simple lamp circuit to plug in. Then replace it with a dimmer switch to see if it works. Be safe. Good luck.