Electrical Query (Metal Breaker Box)

Now that I have established some metal content, I have a question about my screwy house wiring. The knowledge base here is about as broad as it gets, so I figure soembody will have some ideas.

We have an outlet in our dining room that appears to be a 220V 15A duplex outlet. It looks like a regular 110V 15A grounded outlet, except the blades for the plugs are both horizontal. It was presumably installed for a large window air conditioner before central air was installed. It is live, and I measured ~220V AC with a DVM across the two blades.

I'd like to convert this to a regular 115V 15A outlet. I assumed that I would find a dual lever 15A breaker in the panel box, and that I could just connect one of the hot leads to neutral and install a single phase breaker. I haven't had time to take the breaker box cover off the breakers, but there are NO 15A dual breakers in the box.

I'll pop the cover in a day or so when I have time. In the meantime, does anyone have any idea what I should be looking for inside the box that might identify the related breaker? I've got a breaker tracing gadget, but it's designed to plug into a 115V outlet. There is also no guarantee that the outlet & breaker hookup were done correctly. I don't know if the "ground" hole in the outlets is connected to a real ground or neutral, or how to tell.

Thanks for any help or ideas.

Doug White

Find the breaker that feeds it and lift one of the hots and tie it into the common bus instead, Then replace the recept to a normal

110VAC 15A

You should have two breakers that will kill the 220 (or 230 or 240) volts between the two blade connections. There should be a double breaker but it is not unknown for someone to install two separate ones. You should find them feeding conductors in the same cable, one of which may be white. If there is a white, it should become the neutral. If there is not a white, you should apply white sleeving, tape, or other identification to the neutral at both the breaker box and the outlet.

If you are using a digital voltmeter, do not be surprised if the voltage does not go all the way to zero when the breakers are switched OFF.

Don Young

I think Don is pretty much right, but it is also possible that someone has hooked a 15 Amp outlet to a higer rated double breaker. Make sure you mark the neutral white to stay within code and keep the next guy from doing similar head scratching.

Carl Boyd

They are supposed to run a dual breaker with a handle-tie to kill the power to both sides of the circuit if one side trips - but "supposed to be" does not always mean they did.

They could also have used one 15A and one 20A, or two 20A breakers, as long as it has 12-GA or larger wire to the receptacle.

You can make an adapter cord with pin-type test plugs to connect your breaker finder to one hot lead and the safety ground prong - that will send your breaker finder signal back on one side of the 240V circuit. Change the leads to find the other side's breaker.

And if you have a 3-wire circuit in the receptacle box with two hots and a neutral, consider removing the Split Tab on a 20A 120V (T-slot Neutral) commercial duplex receptacle and having two dedicated 120V circuits on the one receptacle. Now you have two 20A 120V circuits available - perfect for a party, put the two 50-cup percolators there. Or let the DJ plug in his sound and lighting systems.

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Doug,

You're talking some serious stuff here. If you have limited knowledge and experience with electrical wiring you're literally "playing with fire" or a potential fire. You commented:

single phase

Did you mean that you thought of connecting a "hot" lead in the junction box to the "neutral" on the duplex to simply use one of the existing wires (probably red color) as the neutral wire? That would be acceptable if you clearly mark it white as someone suggested (Wite-Out or white tape). The other end in the panel would then be connected to the neutral bar after also marking it white. That's acceptable by most codes for a reno.

But first... use your DVM across one hot and the ground at the duplex. If you read 110 volts then you know you have ground. Check the other hot across the ground and you should also pull 110 volts. Now have someone throw breakers until you lose power across each hot side of the duplex and identify the breaker(s) feeding that circuit. Don't ignore any 20 amp dual pole breakers you may have in the panel. Someone may have wired that 15 amp duplex to a 20 amp breaker.

After identifying the breaker(s) and cutting power, remove the duplex and see what wiring configuration you have in the box. If you have red and black "hot" leads and a copper ground you can rewire the duplex to 110 volt by using one hot (use black) to the brass colored "line" screw on the new duplex, the other hot (red now colored white) to the silver colored "neutral" screw. Copper ground wire goes to the green ground screw on the duplex AND back to a ground screw on the box (you may need to pigtail an extra copper wire if the existing one is too short to reach back into the box) . At the panel, your hot black goes to your new breaker, the white (red now colored white) connects to the neutral buss and the copper ground should already be connected to a ground buss. Power the circuit and test it.

If you don't have one, I'd recommend buying a circuit tester for $6.00 at your local home center. It plugs right into the duplex and has a red and 2 yellow LED's that light up to show that the circuit is properly wired (it has a chart printed right on it and it not only shows that the circuit has power but that it's correctly wired and grounded). It'd be a good idea to test all your receptacles with it 'cuz the circuits will work even if the polarity is mis-wired... but they are a fire hazard).

If you find that you have a dual pole breaker with a tie bar, don't be tempted to use only one side of that breaker to power a 110 volt circuit unless you cut or remove the tie bar... which effectively creates two separate breakers. Using one side of a dual pole breaker with the tie bar intact is very dangerous 'cuz if the circuit should short, the spring in the inactive side of the breaker may prevent the active side from tripping. And remember to trip the main breaker when messing around inside the panel box, especially when changing breakers or poking around with a screw driver... I have some melted tools to remind me of the arrogance of working in a "live" panel.

I'm the last guy to ever discourage a DIY project, but when it comes to electrical wiring I'd recommend getting professional help unless you're confident about what you're doing. You, your home and your family are worth the 50 to 100 bucks an electrician would charge to OK your handiwork. (Sorry for the long post but I can't be brief when safety is at issue).

Good luck and let us know how you make out.

Cheers

Michael

If it were me, I'd keep it so I could run my tablesaw in the dining room. Wouldn't the family just love me.

When you remove the coverplate on the outlet, you should see a black and a red wire (both hot, 110 volts each), a white wire (neutral) and probably a bare or green wire (ground). Each of the hots can create its own 110 volt plug. Not sure how much this would get used in a dining room, but since you have both, you can take the 110 volt outlet and split it (little tab between the screws on the hot side) and get each plug on its own circuit. My shop is wired this way, so that I can plug in more tools and not blow breakers (since in a given receptacle, the two plugs are on different circuits). This is convenient when I want to run, say, the 12 amp dust collector and the

11 amp router or circular saw at the same time

Sorry, wrong newsgroup. It's for a TIG welder in the dining room.

It's unlikely that there's a white neutral wire in addition to the red and black "hot" wires. The OP said it was a 240 volt circuit to power an air conditioner so there's no need for a neutral in that circuit. In fact, I wouldn't be surprised if he finds Romex, Lomex or any other standard NMW10 cable in the box with a black and white feeding the duplex... hopefully the white was color coded to red at both ends. A "three conductor" cable (black, red, white {the copper ground isn't included in the count} would typically only be used where 110 and 240 are required at the same time; such as a stove (240v heating elements and 110v clock/controls/light) or an electric dryer (240v heating element, 110v motor/controls). Your shop wiring configuration is another example where three conductor is used, so as to split the top and bottom of a duplex as you explained. Split duplex's are also code requirements for kitchen counter plugs in most jurisdictions.

This is pretty close to what I found. I popped the faceplate off the outlet, and checked it with a flashlight. There's a black wire going to one side, a green wire going to ground, but a WHITE wire going to the other side. No sign I could see of red tape or other indication that it's not a neutral. So much for wiring to code... The wires look to be

12 gauge, but it's hard to tell. They just look a little beefy to be 14 gauge.

At the breaker box, I found a dual 20 amp breaker that wasn't labeled. I flipped that, and sure enough, the outlet (both sides) goes dead.

So, I've got what appears to be a 20 amp 220V circuit with a 15 amp outlet & wiring incorrectly color coded. I'll get a single 20 amp breaker, move the white wire in the breaker box to neutral, replace the outlet & I should be all set. I haven't taken the cover off the breaker box yet, and my only concern is having a long enough neutral wire to reach. My recollection is that splices in the box are a no-no.

Thanks for all the suggestions & ideas. It didn't turn out to nearly as weird as it could have been.

Doug White

Do not use a single 15A outlet on a 20A breaker. Assuming the wire is 12ga, use 15A or 20A breaker and outlet together.

Don Young

A 20A breaker feeding a single DUPLEX outlet is legal as far as I know, unless that's been changed. (as long as the wire is 12 ga)

If the wire is 14 ga then it has to be a 15A breaker anyway.

Most inspectors I've run across will pass one or two splices in the panel, as long as its "neat and workmanship like".

Thank You, Randy

Remove 333 from email address to reply.

Randy fired this volley in news: snipped-for-privacy@4ax.com:

I wish our inspectors had that attitude. I ended up (as usual) cutting ONE hot lead too short, before I'd adequately planned where it would end up. (before you ask, no... moving breakers around wouldn't have solved this particular problem...sigh...)

I spliced it with the standard overlapped-wires/crimped ferrule arrangement, did a double shrink-tubing cover (short over the splice, then long over everything), and continued the lead to the breaker.

The inspector failed it, and said, "No splices allowed in the breaker panel; PERIOD!". I had to pull the lead and restring it. No biggie -- it was only fifteen feet to the first outlet box; but I had to tromp down about fifty feet of blown-in insulation to get to the work.

LLoyd

Yep, you got it, all except for the last sentence. Splices in the panel are perfectly fine, as long as there's enough room to make them neatly.

Why bother, just put a junction box beside the panel and label it (after final inspection) "required by the inspection authority." Gerry :-)} London, Canada

For a too short wire in the panel, just use a junction box and a new length of cable, as Gerald mentioned, or mount a handy box nearby, and install a receptacle in it.. always a good idea to have a convenient place to plug in a power tool and/or worklight near the panel.

WB ......... metalworking projects

"Wild_Bill" fired this volley in news: snipped-for-privacy@corp.supernews.com:

Yeah... that's all workmanlike and servicable, but I'd already planned all the outlets, junctions, etc. that I _wanted_ on that wall, and really didn't want to just hack in another for that simple a fix. The drywall work was already finished, too, so boring the top plate for a new run into the attic would have required substantial damage to the work, and subsequent rework.

It wasn't so much the extra work or the damage to the insulation that bothered me as the fact that the inspector was being SO picky about a job that was intrinsically safe, and very carefully (and cosmetically) done right.

LLoyd

The J-box beside the panel is a "pricky" fix for a "pricky" inspector. you must have twisted his tail already for him to twist back like this. This way it often turns into a pissing contest. Gerry :-)} London, Canada