Take nothing for granted when working with Electricity

[bud--]

Hard to remember what is in this thread anymore.

If you are talking about 2 entirely separate circuits to one duplex receptacle (both tabs would have to be broken off), as far as I know it is compliant. (Probably not what nate had in mind above.) Since about 10 years ago there would have to be a "common disconnect" between the breakers, which could be a handle tie.

Somewhat common is an "Edison circuit" (common neutral) that connects to a split-wired receptacle. Same comment on handle tie, plus since the

2008 NEC "Edison circuits" have to have a "common disconnect".

[bud--]

Split wired receptacles would almost always be wired with an "Edison circuit". If the tab isn't removed one or both circuit breakers would trip. (Could be improperly wired to circuits on the same leg.)

[Tony]

At an old job there were about 5 receptacles on the same circuit/s that were on 2 breakers. Scary to think who did what and WHY?

[terry]

Yes; on two separate single pole breakers! Maybe it was a mishearted attempt to get the advantages of Edison wired outlets without the third wire???? i.e. some sort of 'heavy loads'!

[Tony]

Ran out of 30 amp breakers and 15 amp were on sale?

[auggie]

in mn it was common practice to have the upper half and lower half of outlets in kitchens on seprate circuits somthing to do with the draw of old appliances

[Nate Nagel]

that could actually explain it, someone replacing a recep wired like that without breaking the tabs, I didn't think of that.

nate

[Jules]

Yeah... we just have some "interesting" wiring, that's all - and the fusebox above the bath/shower in one bathroom with a thin wooden cover over it held on by one screw was just beautiful :-) (We weren't using that bathroom, but didn't even know there was a fuse box there until the cover fell off with a loud crash one day)

cheers

Jules

[terry]

Hard to remember what is in this thread anymore.

Yup: Lot's of info and experiences though.

And personally hope am never too old to be corrected, or learn something.

[Shaun Eli]

When I went to put GFCIs in my kitchen I discovered that one double outlet had each half on a different circuit. I used the radio technique, then even plugged in my circuit tester to confirm the power was off (under the unlikely chance that the radio broke when I flipped the breaker)... and still sparks flew! Now I know to test every single outlet even if they're both in the same box.

[DerbyDad03]

re: "Lot's of info and experiences though"

A neighbor asked me to replace the light fixture outside his front door.

"Is the power off?" I asked.

"Yes" came the reply.

I replaced the fixture and ask him to turn the power back on. Instead of going down into the basement, he walked towards me and flipped the switch that was right inside the front door.

I guess his idea of "power off" was a bit more lenient than mine.

[Ralph Mowery]

All I would have done was to cut off the same switch. It goes to the same wire , just closer to the light. Just make sure no one else is around to turn on the switch.

As an electrician in a plant, I often just turn off the switch of the room I am in changing ballasts in a room. I do have a locking device I use to keep anyone from just walking in and flipping the switch. Most are not the normal 120 volt units, but they run on 277 volts. As there are usually 3 circuits on the same neutral you have to be careful not to cut into the neutral. To make things really safe you have to cut off 3 breakers and make sure you get the correct 3.

[aemeijers]

In a residential setting, I'd never trust the switch without testing with a current detector. Some idiot could have the switch leg on the neutral side up in the ceiling box. When I replaced the 2-hole outlets here with 3-hole (grounded boxes), half of the outlets were wired backwards.

-- aem sends...

[Ralph Mowery]

I never trust a switch without testing the wires I put my hands on. If I can make a direct connection to the wires, I like a voltmeter or maybe a circuit tester I have made by Fluke. If I can not make a direct wire connection I use one of the 'hot sticks' that glow when near wires with power. Even If I see someone test the wiring, I do it myself before touching anything.

If you think residential wiring can be bad, you should see some comercial plants that have anywhere from the 120 volt up to 13,200 volt stuff. Most of that wiring is not even inspected like a house would be.