Electrical Load Question

[Joe Pelonio]

In my shop I neeed better light. I have two fixtures with two bulbs each mounted on the ceiling with a wall switch currently, and it's #12 wire.

Can I replace one with a 4' track and four 75 watt halogen floods, and the other with a two-bulb 40 watt 4' flourecent fixture, or is that too much for the wires?

[Jason Beam]

12ga wire can handle "up to" 20amps - watts = amps x volts so amps = watts / volts. 380w @ 110v = about 3.5 amps.

You're WAY fine, Joe.

[Joe Pelonio]

Thanks, Jason!

[Cliff Rohrabacher]

You can put a whole bank maybe four or five 4-foot double bulb fluorescents on a 12-Gauge-wire 15-amp circuit and still have enough voltage to install a dual receptacle.

However since the wire is 12-Gauge I'll bet the circuit is 20 amps which has even more carrying capacity yet still than a 15 amp one.

[Jim Becker]

But...what else is on that circuit? ;)

[Joe Pelonio]

Ah, there's a question. I can answer it because I knocked out the breaker once. It has two computers and assorted peripherals, the laser and exhaust fan and my stereo. What put it over the hump once was my small air compressor that I use for airbrushing and cleaning the laser. Now I make sure other things are off before using it.

[Jason Beam]

But...what else is on that circuit? ;)

Aha! The 6,000 dollar question!

[Jim Becker]

Ah, there's a question. I can answer it because I knocked out the breaker once. It has two computers and assorted peripherals, the laser and exhaust fan and my stereo. What put it over the hump once was my small air compressor that I use for airbrushing and cleaning the laser. Now I make sure other things are off before using it.

That changes a lot. Were I you, I'd put in a fresh circuit for your lighting as all that stuff is going to greatly reduce the amount of lighting you can (and should) add when sharing. There are practical reasons for having the lighting separate, too...especially if you do trip the breaker that all that other stuff is on! ;)

[Joe Pelonio]

Luckily the shop is over the garage where the panel is, and I have unused circuits. I think I'll look for an electrician though.

[Cliff Rohrabacher]

Ah, there's a question. I can answer it because I knocked out the breaker once. It has two computers and assorted peripherals, the laser and exhaust fan and my stereo. What put it over the hump once was my small air compressor that I use for airbrushing and cleaning the laser. Now I make sure other things are off before using it.

Ohhh you didn't say it was already at or near it's limit.

[Rob Russell]

Luckily the shop is over the garage where the panel is, and I have unused circuits. I think I'll look for an electrician though.

Adding a new circuit isn't difficult. Hiring an electrician will probably cost several hundred $$$, you could DIY for under $50.

[Russ Filtz]

+1 for DIY! I actually like running conduit and wiring. But I also like sweating copper pipes too! Don't do it that often, so it could get old if I had to do a lot of it. I ran my own subpanel into my garage in my last house. Had to pull permits and everything (not sure if I HAD to, just wanted to make sure I did it right!).

Current house I only had to splice into an old dryer outlet in the garage to extend a 220 outlet for my TS.