Opened an electrical socket up
Been adding GFCI sockets to a bunch of outlets in my new house.
Came across this weird outlet. The left cable has three wires: black, white and red. The black and red are *both* hot. The right cable has only white and black.
I'm assuming this is the most upstream outlet in the series because it's physically closest to the breaker, but can't be sure until I start clipping wires, which I'd rather not do yet.
The rest have been pretty easy. This one's just odd. What's going on?
May 16th, 2017 1:33pm
Is this how you would wire the outlet if you wanted to control it with a switch? There's no switch control for it. Maybe someone ripped that feature out but left the socket wiring as-is?
May 16th, 2017 1:55pm
They are not two different phases, are they?
Wiring for 240v.
May 16th, 2017 2:08pm
What's the way forward for my GFCI project? Cap the red wire and splice into the black one?
May 16th, 2017 2:09pm
It's not clear from the photo what's attached to what.
Is your house ungrounded? Two prong outlets, or two prong plus disconnected ground prong (not to code)?
This is often where people say they are installing a bunch of GFCI, because adding GFCI to an ungrounded outlet is a code acceptable way of upgrading older ungrounded outlets, whereas just putting a 3-prong outlet and not connecting the ground, which a lot of people do, is illegal.
Presumably this outlet has 120V output when you check it right?
It looks to me like this outlet is inline with a circuit, so for each in there's an out that goes to the next one.
May 16th, 2017 2:33pm
Left cable: white, red and black.
Right cable: white and black.
* left white to socket to right white
* left red to socket
* left black to right black
and yes, installing GFCI because these are ungrounded.
Plan is to cap the red, and go left black/white to socket to right black/white
May 16th, 2017 2:54pm
Wabi, do me a favor. Can you call an electrician to do a check throughout the house? I have a feeling of DIY from previous home owner.
May 16th, 2017 3:01pm
The people I bought it from put new 3 prong outlets on without upgrading the wiring. But this was caught in home inspection so... chipped $1500 off after getting an electrician quote to fix 😎
May 16th, 2017 3:04pm
"The people I bought it from put new 3 prong outlets on without upgrading the wiring."
Yeah this is a common DIY "upgrade" one finds, and illegal, dangerous, ineffective, etc.
A lot of old houses particularly before around 1960 or so have 2 prong outlets and wiring with no grounding. Leaving it alone is sort of fine, and is legal, since no one is fooled into thinking it is grounded. Rewiring the entire house with ground is also OK. But putting in grounded appearing sockets without grounding is a code violation and presents a risk.
"But this was caught in home inspection so... chipped $1500 off after getting an electrician quote to fix"
Was he quoting $1500 to fix it all? Rewiring the whole house and replacing the box will run more like $10-$15k. Probably he was saying he'd put in all GFCIs for $1500 then.
So yeah your white is obviously the neutral here. And black is hot. Both black and white are continuing from the source on the left to the destination on the right, this socket is just a waypoint in a daisy chain. The interesting part is the red. Probably this is the other phase for a 220V. You could confirm if true by measuring the AC voltage between red and black and see if it is 220-240V. So this may have once had a 220V outlet here for a space heater, AC, dryer, who knows. And then when they "upgraded" to 3 prong they randomly tried stuff until it worked.
- verify it's 220V
- cap the red.
- tap from the black instead.
Also, this sort of in line daisy chain thing often you screw both blacks on the small prong side of the outlet, both whites on the other side, rather than this thing where there's some old electrical tape and a short length of wire. Assuming you have enough length to work with there.
May 16th, 2017 3:57pm
Yeah, Pestular Croaker is right. Hire a pro to determine exactly what is going on. I took a look at your picture. The black fabric and silver fabric romexes, plus the cloth electrical tape covering the splice, are absolutely 1950s vintage stuff. Who knows what flaming moron DIY types did in the intervening years?
May 16th, 2017 5:04pm
Actually WorldRover said hire someone. I said I agreed with his plan, but only after verifying with a voltmeter that it's 220V from red to black, so you're sure what's going on.
Also the GFCI will have an input side and output side so the one with the red wire is the input side.
The output will be the rest of the circuit in the house that is on that one circuit and will be protected by that GFCI, so you only really need one GFCI per circuit, and you catch each at the first tap.
The reason GFCIs work for this is they trigger if there is current to the ground. Current in from hot should go out to neutral. Current to the ground means there's a short. If there's current to the ground and the ground is not connected, then current is probably going through user.
May 16th, 2017 5:18pm
If it's 115 VAC, then the red wire is usually a 'switched' wire.
If it's 220 VAC, then the red wire is one phase, the black wire is the other phase, and the white wire is supposed to be neutral.
It's possible to have the top socket switched, while the bottom socket is 'hot' all the time.
If it's 115 VAC, then black is 'hot', while white is 'neutral'. Green is used for a 'wired ground', if there IS a green wire.
All GCFI does is make sure the current going out the white wire is balanced by current in the black wire. If they're unbalanced, that means SOME current is going out the socket, through a human, to ground some other way -- and the GCFI interruptor cuts the power to that socket. There's nothing "magically" protective about GCFI -- it's usually used in bathrooms and other wet places, where a wet human being might ground themselves to a water pipe. In normal wall outlets, it serves little to no purpose.
In the picture, it looks like the red wire is 'hot', the black wire is a feed-through to the next outlet, and the white is neutral.
Too bad you didn't show the pattern on the socket, 115V is a different pattern than 220V
> There's nothing "magically" protective about GCFI -- it's usually used in bathrooms and other wet places, where a wet human being might ground themselves to a water pipe. In normal wall outlets, it serves little to no purpose.
According to the latest NEC code you can't put a 3-prong receptacle on an ungrounded outlet unless it's GFCI.
May 16th, 2017 9:50pm
I wouldn't wire up the GFCI output to downstream connections. It is safer to replace every outlet.
You could switch off the breaker to the black lead to see if the red is also switched off. If they are on the same circuit it doesn't matter which, red or black, you use.
If they are different circuits, someone tried to save some wire by sharing a common white on two circuits. Either way you wire it, you lose. Probably best to wire the new the same as the old.
May 17th, 2017 8:36am
I wouldn't hire an electrician if I were you. You are smarter than at least 95% of all electricians. And none of them care about your house as much as you do.
May 17th, 2017 8:39am
But for heaven's sake, go to Home Depot and buy a book on house wiring. It's not rocket science.
May 17th, 2017 9:30am
Book? When there is Wikipedia and YouTube?
May 17th, 2017 9:36am
Because when your electricity is fucked up, you don't HAVE facebook and twitter.
May 17th, 2017 9:36am
Or Wikipedia or Youtube.
May 17th, 2017 9:37am
I have a smartphone.
May 17th, 2017 9:37am
Well then, you're well situated, you don't need a book.
Then again, you're not opening up wall-sockets.
May 17th, 2017 9:39am
Wabi-Sabi obviously understands this all fine already.
You guys saying he should hire someone, did you notice he already did that? The new guy is going to do something different than tell him it'll cost $1500 to replace the outlets with GFCI?
Hubble, you're still not even aware that GFCI is used under the code to deal with ungrounded houses. You don't know even the basics. Why do you keep giving your advice?
May 17th, 2017 9:51am
Depends on the country, but if you later sell the house and the surveyor sees the wall sockets have been updated could certification of the work done be requested?
May 17th, 2017 10:14am
I replaced all the outlets in my mother's house so we could sell it after she died. It was pretty easy work. I can't imagine paying someone $1500 for work I did myself in a couple of days.
So, yes, I am experienced opening up wall-sockets.
May 17th, 2017 10:22am
"could certification of the work done be requested"
Yeah, but no licensed electrician in his right mind will agree to sign off on homeowner repairs.
May 17th, 2017 1:22pm
It's not necessary though. There's no records of this stuff and so you can just fix it and then claim it was that way when you bought the place if asked.
This stuff in the US is as-is. Buyer has the right to have licensed inspectors check the stuff and bail out if desired before a certain date during the offer period.
The only thing with a decent paper trail in most places is septic systems. In most counties, these have to have plans filed for any changes and the inspector has to come out and make sure it's ok before backfilling.
Lots of places require permits for repairs but when they are interior repairs who would know if you did or didn't.
May 17th, 2017 1:25pm
"I replaced all the outlets in my mother's house"
Legion, did you simply replace 2 prong outlets with ungrounded 3 prong outlets or did you add GFCI outlets?
May 17th, 2017 1:26pm
GFCI all the way, every outlet.
I was able to ground a few of them, so even better. All the boxes were metal, and there was a single bare copper wire running from box to box, grounding the boxes. Many of the boxes did not have a ground connection, so on those I didn't run a pig tail from there to the outlet ground lead.
May 17th, 2017 7:43pm