110v garage circuit on a 220v breaker?

You guys always seem to have good insight on just about everything... so maybe you can shed some light on this one...

I'm renting an old house (read, at least 75 years old) and all the electrical is grandfathered... so there are a lot of really strange and bizzarre things going on in this house as far as electrical setup is concerned... as far as I can tell anyway.

Anyway, I went to go check to see what amperage my garage 110v circuit is rated at... and this is what I found.

Here is a pic of the breaker, the description inside the panel... and when I switch the breaker, this is the plug that loses power.

What do you make of this?

#28 - garage

#28 & #30

the 110v outlet that loses power when the breaker is opened

No sub panel in the garage? If not, its probably illegal, but it will work. A 220 plug is just 2 -110 circuits- one from each side of the ....the....thingy that has two sides to it., plus the neutral. That plug is either using just one side, or its hooked to one circuit on the top, one on the bottom. Both will be 20 amps, which I think has to be a special app- 15 amps is normal on a wall plug. Thats also a ground fault plug.

As you can tell, I'm a properly trained up electrimatician.

Be sure not to accidentally stick a peg hook into the outlet, that would be bad, Mkay?

No sub panel in the garage. Both outlets go out when the breaker is flipped. Definitely illegal... but the house is grandfathered so it's "okay."

The main reason I am investigating this is to see if it would be easy to get 220v in the garage for a welder.

Also, I will be very careful to not stick any peg hooks in the outlet. That could be... ELECTRIFYING!

IMO, That outlet is probably only using one leg of the breaker. This is based on the fact that it is a GFI outlet. I would have to pull the panel cover and the outlet to be sure.

Agreed. It looks like they used the A and B from that breaker to feed seperate outlets. Not ideal, but I've seen worse.

As mentioned, running power for a welder is a little more involved than looking at the existing breakers in your panel.

The house may be 75 yo, but the breaker box is current, and the outlet is new style. The scariest electrical stuff I've come across is in systems like that. Some jackleg mechanic goes in to re-do the electric with no real knowledge, much less a license, and the end result can be quite dangerous. At least they labeled the breakers, I've seen too many without any. I strongly suggest having a qualified electrician look at it. When we moved into our current house, I found that the waterheater was running on 110. I had a pro take care of that.

here's a stupid question. If each plug is on a separate circuit... couldn't I run two 110v stick welders (rated for 20 amp circuits) with the leads in a parallel without tripping the breaker?

Mmm. Don't know if I would attempt that. I ran across a problem with a 220V dryer some years back, it would tumble but the heating element didn't work. The heating element etc ohmed out perfect, the breaker flipped and made all the right sounds but still no heat. Turned out there was a bad contact inside the 220V breaker, yet it didn't trip. So I would not count on one side of that breaker tripping the other if something flinky happened. That could definitely make your hair stand up.

The easiest (and safest) way to fix what you have there (assuming you have no need for 220V) is to yank the 220V breaker and replace it with a pair of 110's, thus creating two 110's from a 220. That's assuming the box is wired properly for that.

Each 110 needs: hot (black), neutral (white) and a ground (green or bare). 220V 3 wire is black (hot) white (hot), green or bare (ground). 220V 4 wire is (or should be) black (hot) red (hot) white (neutral) green or bare (ground). I have never tried any weirdness like sharing neutrals at the wall for two different circuits, I guess it would work but somehow it gives me the heebie jeebies.

Both my 110V welder and plasma cutter require a minimum of 15 amp 110V, the plasma cutter wants a 30 amp 110V or 220V for max cut. If I run the PC at the top of the 20 amp 110V range it will pop the breaker. It's an automatic adjust 110/220V unit so if I'm cutting thick stuff I run it off of 220V.

All the wall outlets in my shop are wired for 20 amp 110V, the lights are on 10 amp 110V. The 3 220's (compressor, A/C and plasma cutter outlet) are all 30 amp.

Some years ago a co worker bought a house which had a shop in the back, he noticed that all of his power tools ran really well. That is, until his drill burned up. So he went poking around and found that every standard 110V outlet in the shop was really 220V.

Jensenman wrote: Some years ago a co worker bought a house which had a shop in the back, he noticed that all of his power tools ran really well. That is, until his drill burned up. So he went poking around and found that every standard 110V outlet in the shop was really 220V.

haha that gave me a good laugh

"Say George, did you say this was a 3600 rpm grinder?" whizzing away at 30,000 rpm

Oh, he's something to think about. When I run my compressor and my shop vac off those two plugs, if I sandblast for a while the breaker will trip.

But if I plug the compressor into that circuit, and then the shop vac into the lighting circuit, neither breaker trips.

I think that sort of in a round about way answers my question about running two welders in parallel off those plugs.

You can't split a GFI recepticle into two different circuits. I would pull the panel cover off and take pictures of the inside.

thats not a 20a outlet either

pull cover and pull outlet out of box and look at things, and pull cover off the main panel. you may find they only have a black lead at one terminal of the breaker.

old house electric that has been messed with by years and years of unqualified old guys can get scary.

Sounds like it may be a multiwire branch circuit. One pole of the circuit breaker feeds one circuit, the other pole feeds another circuit, and the two circuits share a single neutral wire. Since the two hot wires are 180 degrees out of phase, the neutral wire can handle the return current for both circuits. They're most often seen with split wired duplex receptacles in one area of the house, (say, the kitchen or garage) where in each duplex receptacle the two outlets are one two separate circuits. One problem with them is if you have too high a load on one circuit and pop the circuit breaker, both circuits will go dead.

Here's a synopsis: http://www.inspectapedia.com/electric/multiwir.htm

Edit: someone mentioned the outlet is not rated for 20 amps; the National Electric Code allows the use of 15 amp receptacles on a 20 amp circuit, as long as there is more than one of them (and a duplex receptacle counts as two.) There may be local regulations prohibiting them, however.

that may be true.. but it still needs a 20amp outlet to be safe.

You've gotten some good advice here, but some not so good. It's pretty jumbled up.

You have 2 issues to deal with. The welder, and the current wiring.

The simple answer is that the wiring is COMPLETELY UNNACCEPTABLE for a welder. Wonkothesane got the closest when he told you you need to run a heavier wire. Of course, you never told us the distance or the load of the welder you want to buy, so no one can tell you the wire size.

Now for the current wiring... you've got a fire waiting to happen. While I would agree with Ian F that it is not the worst I've ever seen, that is NOT a current panel box (it's 30+ years old), is NOT properly labeled (were does circuit #30 go?), and is NOT properly wired (circuit #28 an #30 are tied together). Jensenman got closest on this one when he described the bad contact inside the 220V breaker that wouldn't trip.

You've got a 220V breaker on (2) 110V circuits. It is NOT safe. The problem is that if one circuit faults, it will likely not be strong enough to trip both legs of the 220V breaker. this would leave both circuits hot and shorted- fire. The GFCI helps a little, assuming it is wired correctly, which is a BIG assumption. It is not (just my gut feeling, which is usually VERY accurate). I'd bet good money there is improper grounding all over the place, and likely aluminum wiring tied up in that panel.

Throw all your crazy ideas about running a welder off the two separate legs out the window, unless you are prepared to burn the house down. BTW- if you DO burn the house down, there is a good chance YOU could be liable, now that you've confessed a willingness to overload the circuits and operate equipment not suitable for the circuit.

You are ALREADY overloading the circuits with your compressor. That's why it's tripping. Stop trying to come up with a work-around and take the warning signs.

Stop guessing. Several people have already said that no further information can be given without pulling the panel cover and/or outlet. It's not "OK" because it's been grandfathered. It's unsafe.

Call the landlord to fix the wiring PRONTO. While a real electrician is there, talk to him about proper wiring for your welder.

Diagnosing electrical problems over the internet is about as smart as getting a cancer diagnosis and treatment at the local laundromat.

Taiden wrote: here's a stupid question. If each plug is on a separate circuit... couldn't I run two 110v stick welders (rated for 20 amp circuits) with the leads in a parallel without tripping the breaker?

You DO NOT know those are 20A circuits. What you know is that there is an improperly installed 20A 220V breaker. you have not checked the wire guage, distance, condition, or amperage draw.

It is likely they are 15A circuits.

So, the answer to your question is "NO".