Novice Electrical Question

[Glenn Samuels]

I am wiring my new shop for 220 power and using dedicated lines for each receptacle. I have a planer and a jointer that each require 20+amps. I am using double pull 30's and 30 amp receptacles for safety. Here is my question. Because I am using double pulls, do I need a 10-2 or 10-3 romex? I don't know if I need 1 hot for the double pulls or do I need 2 hots since there are two breakers tied together.

[Von Bickley]

You will need 10-2 with ground.

You will have 2 hot wires. One wire to each side of the breaker.

[Ole Anderson]

To add just a bit to the previous post, based on your 1 vs 2 hots: The wire will have 2 hots, one from each leg of the panel (there will be 2 connections on the paired breaker), with one ground and no connection to the neutral bus. When you say "pulls" are you speaking of breakers or pull style fused connections?

[Glenn Samuels]

To add just a bit to the previous post, based on your 1 vs 2 hots: The wire will have 2 hots, one from each leg of the panel (there will be 2 connections on the paired breaker), with one ground and no connection to the neutral bus. When you say "pulls" are you speaking of breakers or pull style fused connections?

I am referring to my breaker box.

[Art Mann]

I think when the original poster said "double pull" he really meant "double pole". His post is easier to understand when you read it that way.

[Ryan Mooney]

10-2 works fine for a 30 amp 220 run up somewhere under 100 feet (further than that the voltage drop starts to be significant - lookup "wire distance calculator" to get some idea of what your limits are). You should however clearly mark the white wire (normally used for neutral) as the second Hot. A simple way is a couple wraps of electrical tape where it enters the box, another wrap an inch before the breaker and then a wrap on the side in the outlet box. That may or may not pass inspection in your jurisdiction (so if you're doing inspections ask first before you spend $$'s on the wire) but suffices in many (most? dunno anymore..).

If you're running inside conduit you can't (reasonably) use 10-2 romex, but "must" use separate strands ("must" is not entirely true in all cases, but the exceptions are sufficiently limited and overly complicated to explain so its not worth worrying about them). In that case you would want red, black and green strands.

[Wade Lippman]

At the risk of being rude, are you sure you want to do your own wiring? It isn't rocket science, but if you have to ask how many wires you need....

[Art Mann]

At the risk of being rude, are you sure you want to do your own wiring? It isn't rocket science, but if you have to ask how many wires you need....

I agree. Maybe you have a friend who is knowledgeable and can give you some local advice?

[Roger Feeley]

One of the smarter things I did when I set up my shop in the basement was to have a licensed electrician install a 60amp breaker in the main box supplying a load center. There is a big shutoff lever by the load center so I can easily shut down the shop power when I work on it. I have the original basement lights and an outlet for portable lighting for when I am messing around in the load center.

Having that load center has given me a lot of peace of mind. Everything upstream of that load center belongs to the pro's. Everything coming out of that load center is wired by me.

[Ole Anderson]

You are right, wiring 220 v doesn't take a rocket surgeon, or is it a brain scientist? :-) How did we learn? By someone explaining it to us. And once that light bulb went on and we understood that 220 is just two opposite 110 circuits slapped together, we knew how to do the basic wiring for a 220 circuit. And this forum is a good a place to learn the details as most others. And we learn by posting "dumb" questions. If course no question is dumb, but sometimes we have to sort out the dumb answers, but usually we get plenty of help here doing that.

[Duane Meadows]

If course no question is dumb, but sometimes we have to sort out the dumb answers, but usually we get plenty of help here doing that.

The problem is, if you don't already know the answer, how exactly do you "sort out" the dumb answers from the good ones? Look at any of the threads on electrical wiring and you see a 50/50 split(some times 25/25/25/25!).

Any of the borg stores and your local library carry books on basic wiring. They may not be 100% all the time, but are usually better than the arguments that every such question seems to become here!

Don't get me wrong. I am a contributor because there is a lot of good info on the creek on a wide variety of things and I really enjoy most of it, but frankly, it's the last place I'd go for electrical advice!

PS: Forums in general are the last place I'd go for electrical advice.

[Wade Lippman]

The problem is, if you don't already know the answer, how exactly do you "sort out" the dumb answers from the good ones?

I sort of agree with you. There is a lot of conflicting advice, but it is easy enough to pick out the good ones if you have a basic understanding of wiring.

In this case, asking if a double pull breaker needs one or two hots, suggests that basic understanding is not present; and no, he is unlikely to get much help here. Perhaps a book would help. I don't know if you can do electrical work safely based on a book; but I agree that it has to be better than doing it on a basis of a few random questions here.

I have a friend who has a MS in chemistry and an MBA who was very competent in carpentry, drywalling, and plumbing; but had no sense at all of electrical. Several times he asked me to have a look at what he was doing, and I don't doubt he would have burnt the house down left to himself. If you screw up drywalling (witness my first attempt at a couple walls last winter...) it is just unattractive; if you screw up electrical you can die. I wouldn't want to learn it from a book.

(It just occurred to me that maybe I just think he is competent in carpentry, drywalling and plumbing because I know so little about them. Maybe he is just as incompetent on those as on electrical. Horrible thought)

[Art Mann]

I agree that internet forums aren't the best place to learn how to do electrical work but they can point out potential problems and risks that readers can then investigate for themselves. I think the best way to learn good wiring practices is to work with someone who is already competent. That is why I suggested the OP get with a friend who has done electrical wiring to help.

[Julie Moriarty]

It always concerns me when you see a homeowner or weekend warrior answer electrical questions. It may not be rocket science but there's a lot more to wiring a system than making sure the wires are the right size or connected to the correct terminals. I've fixed many disasters left from people who thought they knew what they were doing. Some of them were a short time away from starting a fire. Others wreaked havoc on home electronics. There's really only one right wire to wire a system.

To the OP, you should reconsider tackling this yourself. If you are doing a complete wiring of a workshop with higher than normal loads (normal for the average home), you need to call in a qualified electrician. It could become one of those "pay me now or pay me later" things.

[Sam Stephens]

the confusion comes from the notation: 10-2 = 2 current carrying wires + a ground vs. 10-3 = 3 current carrying wires + a ground. It's obvious when you see the wire. You want 10-2. Wiring a couple of outlets from the main breaker or subpanel is not rocket science. Get a book on simple wiring -borg or the local library. Given what I've seen in this forum as of late, I would be hesitant to ask any electrical advice for fear of inciting another spitting contest.