please explain this wiring - black, red, white, ground

I've replaced light switches before for regular "black, white, ground" setups and 3-way setups. So I was helping a friend who asked me to replace a switch/receptable combo with just a plain on/off switch. I opened up the existing switch/receptable combo and found an extra wire - a red one! I figured it was either a traveler for an old 3 way (I was guessing; no 3 ways were ever seen) or an extra hot. The unit looked like:
SWITCH (top) (toggle left>right) 110 V receptable (bottom)
It was wired like this (the 2 screw terminals on each side):
-- RED BLACK -- | -- WHITE nothing -- (ground at bottom)
I figured white was neutral because it was the only silver screw and the only one labeled on the back to be "white". I didn't have a meter but I had a basic "light goes on" continuity tester. I did "black to white" and the light went on. "Red to white" and the light didn't go on. So I capped off the red one and wired up the new "just plain on/off" switch with "black to white", plus the ground. Flipped the house circuit back on and it popped with a spark. I tried another switch and it did the same thing. I figured it was obviously my wiring but I didn't know why. I put the old switch back together and decided to post here! What am I doing wrong and what the heck is the black wire and the red wire?
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On 30 Jun 2003, FN wrote:

Question 1: is/was the receptacle always hot, no matter what position the switch is in?

Question 2: is there a (removeable) connecting tab between the "black" and "nothing" screw positions? (just like you find on a dpuplex receptacle, so you can make them work independantly)

You're screwing with something that you should probably not be touching. Sorry for the reality check, but one of the first things you need to learn about a common, single pole 120VAC switch (in amy configuration) is that the neutral is NOT involved. You switch (make or break contact) the hot side only!
The white wire is attached to that device to provide a neutral for the outlet - nothing more. When you wired black or red with the white with your switch, you created a dead short of hot to neutral when you flipped the switch.
It's likely (from the way you've described the device) that the black is the supply wire, providing 120V from the breaker, and there is nothing on the "nothing" sccrew because the jumper tab is in place, it is getting fed by the black wire as well.
The red is the switched hot that feeds whatever is controlled by the switch (assuming a light fixture). You mention nothing of the white also leaving the box, going to the light fixture. Does it? (more answer to come, pending your answer to that question.)
TP
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Yes.
Yes. I drew that above, but didn't comment on it. The tab is not broken.

Yes, I didn't write it properly above. But there still has to be a neutral somewhere, right? As I understand it, there's 2 ways to wire a light, either the light is first and the hot drops down to the switch to be broken, or the switch is first and the hot goes up to the light when connected.

Isn't the outlet wiring the same thing as the "dead short of hot to neutral" that I may have done? Why would one trip the fuse and the other wouldn't?

Yes, I also believe that the black feeds the "screw" beneath it.

Only one set of wires comes into the box. Nothing is re-connected to leave the box. So, as I write this (forced to think), I suspect the red is probably the wire that carries the hot back up to the lights? So I need to wire my switch as "black > red" ? If so, where's the neutral in that? As I wrote before, there's nothing else in the box. Thanks for your help.

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On Mon, 30 Jun 2003 16:25:45 GMT, "FN"

It is wire as your second assumption, the light is wired with the power cable going to the light, and the 3 wire +G going from the light to the switch/outlet, black probably hot, red to the light, white for the recepticle neutral, neutral for the light already existing in the junction box.
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On 30 Jun 2003, FN wrote:

Good, that kind of confirms the situation from question 2...

LOL That thing!? Out there in right field?! OK, sorry for the chuckle, I obviously didn't pick it up when I read your post.

Sorry to reiterate, but this is the key: ...one of the first things you need to learn about a common, single pole 120VAC switch (in amy configuration) is that the neutral is NOT involved. You switch (make or break contact) the hot side only!

Yes. But there is a big difference between "being somewhere" and going through the switch! The switch interrupts the hot, ONLY, the neutral isn't part of the connection.

Nope. The "outlet wiring" is connecting the black to one hole on the receptacle, the white to the other side. If nothing is plugged in to it, there is no circuit created, no current flow. Plug in a radio, and you have very little current flow. Plug in a toaster oven, and you're likely drawing 8, 10, 12 amps. Stick a piece of copper wire between the holes (just like closing your switch) and you create a short, it will draw all kinds of current for a fraction of a second, until the breaker trips.


Again, sorry I missed that above.


Yes. The red is the "load" side of the switch, as opposed to the "line" side, which is connected to the breaker.

Yes. The neutral (I had to stop and ponder this one for a minute, as to -why- it's this way) is being fed to the light fixture from -somewhere- -else-. By any chance is this light fixture in a place where there is another circuit??? I'm betting it is. Whoever did the install on this took their white wire from that other location, and ran the red back down to your switch location. It's not the sanest, cleanest way of doing it, and I have no idea if it's up to code, but it will work.
To answer a question from anoher reply of yours further down in the thread: What to do with the white wire after you've used the red and black to wire your switch? Unless it is extremely short, cut the stripped piece off, then screw a wire nut right on the unstriped end of it. That wil keep it safe from contacting other things in the box. Tuck it in the back, in case the next guy down the road wants to restore the switch/outlet combo.
TP --
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wrote:

You should NEVER assume this. Although rare, I've seen cases where the neutral has been switched. And its been in older homes...where there was no color coding protocol followed to speak of.
You should ALWAYS make sure of the actual wiring schematic. When in doubt, turn off the breaker...even the main if necessary.
Have a nice week...
Trent
Help keep down the world population...have your partner spayed or neutered.
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On 04 Jul 2003, Trent wrote:


I told him to "assume' NOTHING.

Oh, well la-di-da. You've "seen" that, huh? You read about it on a web site, I can tell from the generic, squeaky clean "observations" that you offer, that's the extent of your experience, isn't it? I was telling him how a switch IS WIRED. Period. I made no guarantee that the person before him wired it correctly, THAT wasn't the issue AT HAND.

I NEVER told him *NOT* *TO*, jerk.

I don't know what your problem is, but you can lose it, now. Or be treated just like the other leg-humping clowns that twist my words around to be something that wasn't said. If that's what you want, you'll get it.
TP -- _________________________________________ If u are gonna say that I said something, please say what I REALLY said. ($1 Earl)
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wrote:

Actually, you did worse. You told him something that isn't ALWAYS true...although in 99.9% of the cases, it WILL be true. Its that little .1% that can kill you, though.

Pretty much. I look up every post here...pick out the best answers on the Web...then post. I try to do it quickly, though...so's I can make my posts look current and knowledgeable. lol

Jerk? Hmmmmmm...

Sorry...can't do that. It took me too many years to perfect it! lol

Whatever! lol
Have a nice 4th weekend...
Trent
Help keep down the world population...have your partner spayed or neutered.
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Remove the switch using proper precautions. Apply power and neasure voltages to ground. If both the red and black wires are now hot this PROBABLY means there was a dedicated hot wire for the switched circuit and a seperate hot wire for the outlet.. I doubt if this is the case since the switch and outlet were straped together on the original switch. Otherwise if only one wire is hot the other hot colored wir is probably part of the circuit thay goes to whatever is switched. If we assume black has power on it and red doesnt then the black wire would connect to the side that has the strap on it , the red ot the other side of the switch and the white to neuttal connection of the outlet. In this configuration the outlet will be hot all the time. IF you want the outlet switched reverse the connections of the red and black wires.

neutral
broken,
neutral"
leave
to
help.
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On 30 Jun 2003, TURTLE wrote:

Yes, and you're admittong you don't know enough to answer a simple question. (Simple question #2, simple question #1 is "what is a Bell Box?" you failed miserably on that one too.)

And I've given him nothing but good, solid information.

Take a hike, stalking, obsessive jerk.
TP
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This is Turtle.
I have no ideal about what your talking about but OK you know it all Tom. I'm a Licenced Commercial Electrician by the State of Louisiana and do not do mickey mouse job like wiring lites in a house. i run service to HVAC equipment that will draw in amps what a whole house will pull at one time. I do not profess to know the residentiual electrical work very well but i know enough to know when to speak or keep quiet. I see in a bunch of cases you don't know when to speak or be quiet.
Now Tom you profess to know a good deal about residentiual wiring of homes. Here is some questions for you.
1) Have you ever wire a complete home for electrical service? 2) Do you hold any type licences in the Electrical Field? 3) Have you worked in the Electrical field in any manner at All? 4) Do you own more than a VOM and a screw driver? 5) yea , Tom explain to me what a bell box is used for? and no it is not the box that holds the christmas bells to put on the christmas tree. 6) Answer these and it might be interesting to hear. If you don't answer these question here. It will not matter.
TURTLE
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I
know
homes.
Turtle:
Please don't give Tommy Pedophile any more questions to ponder. He is still working feverishly on the previous questions that were given to him about the following topics:
1. Would a smart person pay $80 to change a furnace filter? 2. Why can't you use copper pipe instead of a fuse? 3. What is the difference between a ground wire and a neutral wire? 4. What psychosematicschitzoidembalism is created when breathing PVC fumes?
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On Mon, 30 Jun 2003 07:50:26 GMT, "FN"

Cap it.
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