Electricity 101

A

AKHammonds

Joined
Mar 22, 2007
Messages
52
This in not a knife question, but a shop information question. If I open a 110V outlet it has 3 wires, White (hot), Black (return) and a green (ground). I have a work bench that has 220V run to it but no 110V. It would be very handy to have but for several reasons hard to do. I have been told I take either of the hot 220V wires and the ground (return?) to make 110V. I would assume the one hot would become the white and the return would become the black, but where do you get the ground from? :confused:

Thanks
Allen
 
this can be done but you have some problems with your coding.
Black is the "hot" leg white is the neutral leg and green is ground. What you need to do is open your 220v box and find out how many wires you have in it many time for a 220v drop only there are just three wires. Black, HOT, white, HOT, and green ground. if this is the case then you can't split it SAFELY into two 110v legs. However if there are four wires in the 220v drop then it is very doable.
 
I have gotten that black and white thing mixed up before as to which was hot & which was return, but green is ground the world around....I think:confused:
I will look inside the box as soon as I get home tonight.

Thanks
Allen
 
First things first. Kill all power at the box under your meter before attempting to work on the electrical.

You can split 110V off of the 220V like you described but with 3 wire 220V you will need to get a ground by running a wire back to the grounding lug in the breaker box!

(Refering to three wire 220V )
Black (Hot)
White (Hot)
Green (Ground & Neutral) YOU CAN NOT PICK UP A GROUND HERE WHEN ATTEMPTING TO SPLIT OFF A 11OV CIRCUT FROM 3 WIRE 220V

(Refering to Four wire 220V)
Black (Hot)
White (Hot)
Red (Neutral)
Bare (Ground) YOU CAN USE THIS AS A GROUND WHEN ATTEMPTING TO SPIT A 110V CIRCUT FROM 4 WIRE 220V.

If none of this makes sense please get some one to wire it that knows what they are doing. Make sure all connections are tight and properly wire nutted!
 
Lets start to do some investigating.

IF you have a 4 wire white, black, red, and bare ground a voltmeter check is still required for safety. ..... from black to white should read 110V......from red to white should read 110V.......from black to red will then read 220V and lastly from white to the bare ground will read O volts.

If all of these requirements are met you can get two 110 V circuits and one 220V single phase circuit.............black to white is 110V.........red to white is 110V .........and lastly red to black will give 220V.

REMEMBER TO SHUT OFF ALL ELECTRICITY TO THE CIRCUIT BEFORE STARTING TO CONNECT THE NEW 110V CIRCUITS.

George
 
Guys he should hire an electrician!!! Wouldn't want to see him burn the house down!!lol
you can get 110v regardless number of wires !!! If it only has black white and bare copper/green all you need to do is open your circuit breaker panel remove the white off the 2 pole breaker that is powering it and move it to the neutral bar in the panel and then replace the 2 pole circuit breaker with a single pole 15 or 20 amp breaker.
 
Dixieblade57 said:
First things first. Kill all power at the box under your meter before attempting to work on the electrical.

You can split 110V off of the 220V like you described but with 3 wire 220V you will need to get a ground by running a wire back to the grounding lug in the breaker box!

(Refering to three wire 220V )
Black (Hot)
White (Hot)
Green (Ground & Neutral) YOU CAN NOT PICK UP A GROUND HERE WHEN ATTEMPTING TO SPLIT OFF A 11OV CIRCUT FROM 3 WIRE 220V

(Refering to Four wire 220V)
Black (Hot)
White (Hot)
Red (Neutral)
Bare (Ground) YOU CAN USE THIS AS A GROUND WHEN ATTEMPTING TO SPIT A 110V CIRCUT FROM 4 WIRE 220V.

If none of this makes sense please get some one to wire it that knows what they are doing. Make sure all connections are tight and properly wire nutted!
Click to expand...

Dixie, among others, is correct. A pure ground running to your equipment is a necessity, be it 220 or 110. It's called, strangely enough, an equipment ground and is needed to protect against unwanted power running to you or your machine which can happen when ground and neutral are shared. This is a code requirement in all industrial applications of which I'm aware. It's also the wise course for home workshops. We run into a lot of 3 wire 220 here in the Ozarks and in fact recently re-wired a milking barn to eliminate just such a dangerous situation.

If you are not confident doing the work hire a professional. Send him home with a 6-pack and he will more than likely be happy to teach you enough so you will be able to do it yourself next time :)
 
Dixieblade57 said:
First things first. Kill all power at the box under your meter before attempting to work on the electrical.

You can split 110V off of the 220V like you described but with 3 wire 220V you will need to get a ground by running a wire back to the grounding lug in the breaker box!

(Refering to three wire 220V )
Black (Hot)
White (Hot)
Green (Ground & Neutral) YOU CAN NOT PICK UP A GROUND HERE WHEN ATTEMPTING TO SPLIT OFF A 11OV CIRCUT FROM 3 WIRE 220V

(Refering to Four wire 220V)
Black (Hot)
White (Hot)
Red (Neutral)
Bare (Ground) YOU CAN USE THIS AS A GROUND WHEN ATTEMPTING TO SPIT A 110V CIRCUT FROM 4 WIRE 220V.

If none of this makes sense please get some one to wire it that knows what they are doing. Make sure all connections are tight and properly wire nutted!
Click to expand...

I'm pretty sure that isn't quite right. White is neutral, red is hot. Black is hot, bare or green is ground.

In foreign machines, green with a yellow stripe is neutral, blue black and brown are hot. In the US, blue is hot on a three leg.

White is commonly uses as hot, but that does not meet code. White is neutral. If a white line is to be used as hot, it is supposed to coded with a hot color tape (blue, black or red)
 
You can use ground as neutral, but it can kill you too...
 
White is commonly uses as hot, but that does not meet code. White is neutral. If a white line is to be used as hot, it is supposed to coded with a hot color tape (blue, black or red)[/QUOTE]

Thanks Nathan for pointing that out . Face taping a neutral when used as a hot leg is very important . I will save the life of those who do not use a meter to check voltage .
 
Okay...
For once in my bladeforums career I can be of some help.
I am a journeyman electrician :D
Nathan the machinist is correct.
Ground must stay ground. Even though neutral and ground go back to the same place in the first service panel in a house. Usually it is not in as good of insulation as the current carrying conductors.
ALWAYS color code your wires correctly.
White = Neutral
Black and red are Hot or Power. (in homes)
If you make one of your Hot wires into a neutral just tape it white on both sides.
Anyways, Nathan has it right. :D

If you do not have proper tools (tester) to ensure you are doing it correctly just hire an electrician, it should be a cheap and easy job for an experienced one.
 
Dixieblade57 said:
First things first. Kill all power at the box under your meter before attempting to work on the electrical.

You can split 110V off of the 220V like you described but with 3 wire 220V you will need to get a ground by running a wire back to the grounding lug in the breaker box!

(Refering to three wire 220V )
Black (Hot)
White (Hot)
Green (Ground & Neutral) YOU CAN NOT PICK UP A GROUND HERE WHEN ATTEMPTING TO SPLIT OFF A 11OV CIRCUT FROM 3 WIRE 220V

(Refering to Four wire 220V)
Black (Hot)
White (Hot)
Red (Neutral)
Bare (Ground) YOU CAN USE THIS AS A GROUND WHEN ATTEMPTING TO SPIT A 110V CIRCUT FROM 4 WIRE 220V.

If none of this makes sense please get some one to wire it that knows what they are doing. Make sure all connections are tight and properly wire nutted!
Click to expand...


Not to be a stick in the mud but this is wrong.
Black (common or hot)
Red (Another hot wire most of the time with 220v or in a 3 way switch system)
White (neutral in a 220 setup / but can sometime be a hot wire in a multi switch system)
Green or bare copper (is always ground)

People get hurt when they start messing with the NEC. If you have questions or doubts always refrence the National Electrical Code book you can google it and get most electrical answers.
 
While these guys are correct. I got one thing to say. Insurance. If you do your own wiring, don't get it inspected and there is a fire. Well, start praying. Electricity isn't hard to work with as long as you know what your doing or have someone who are trained do it.
 
There is a lot of misinformation (and plain wrong info) in this thread. Rather than point out any one, I'll just say Slimshanee has it right. Period. In the US at a properly wired power outlet, white should always be a neutral, green or green/yellow should always be a safety ground, and red + black are always hot wires. Wiring between switches and lights or ceiling fans are not at issue here, but even then white should always be neutral, green a ground, and black should be hot. (If you need 2 hots to get power to a fan and light, for example, use blk and red, not blk and white).

It is legal but not recommended to use colored heat shrink tubing or tape to identify/change the wire colors at termination. It isn't worth it IMHO.

Note that in some countries this is different. Euro style 230 VAC is single hot, 230 V from hot (blue) to neutral (brown). American 220 V is always 110 hot to ground and only 220 hot (black) to hot (red). In Mexico many people use white as their hot and black as neutral. I dunno why but here in S. Texas we run across it all the time when backyard Mexican 'electricians' are at work.

I make a living engineering power systems of all types (though mostly 3 phase industrial we still see a lot of single phase) and worldwide codes (NEC in the US, ATEX in the European Union, CSA in Canada, etc.). I know, never trust the engineer, but I'm siding with the electrician so that should count for something!:p

Systems are designed this way for many reasons. Sometimes the ground is undersized (as allowed at times by NEC). Sometimes it only has a paper tape for insulation. GFCI outlets and breakers depend on the imbalance of current flow between hot(s) and neutrals via the ground path. All of these are examples of pitfalls where not keeping to the standard can cause trouble or serious hazard.

To the original question: Splitting a 220 4 wire outlet into 2x110 outlets works, but the breakers are tied in the panel so when one trips they both go. Also, most household 220 outlets are higher amperage, so you will be plugging in a device with a cord sized for 20 amps max into an outlet protected by a 30-70 amp breaker. It is entirely possible for the cord to melt (explosively, arcing molten metal everywhere and starting fires) before the breaker trips. That's why there are dozens of unique outlets matched to voltage and amperage in the NEMA outlet chart.

Power cords make lousy fuses. Skin is a terrible insulator. Stay safe guys!
 
what slim said
which is funny cause i'm a master electrician, great slims think allike!
if you still need help pm me and i'll email you simple a wiring diagram
 
Always refer to the NEC like I said before, It will never lead you astray. I also use a little hand book when I come across a problem that I either cant remember the answer or need to double check, Uglys Desk Reference for electricians. Usually when I cant remember the load formulas or wire size for a legnthy run.
Ive been doing electrical work since high school 20+ years now and have seen some people get hurt really bad by electricity, If you dont know what your doing or do not feel confident in doing the work get some one that does know to help or do it for you.
 
I agree. Do your research or get a competent individual to help before doing anything.

I'm confident enough to wire up my new shop, just finished it yesterday(tues). 4 circuits, 11 outlets, 2 light boxes, 2 switches and main breaker box.

Nothing major, but still something to have respect for regardless if you are wiring an entire building or changing a faceplate.
 
I would like to add 2 things here:

1) Hot is hot. Neutral is neutral. Ground is ground. These may or may not properly coorespond to various colors.

It is true that "In the US at a properly wired power outlet, white should always be a neutral, green or green/yellow should always be a safety ground, and red + black are always hot wires" - but the key word here is SHOULD. One of the worst things you can do is assume that your wiring was done properly.

2) You said "I have gotten that black and white thing mixed up before as to which was hot & which was return"

In the 220 V scenario, where there are two "hots", remember that this is AC. Each "hot" is out of phase - when "hot 1" is at +110 V, "hot 2" is at -110 V. The resulting voltage is 220 V. At any one moment, one "hot" is behaving as a hot, and the other "hot" is behaving as the neutral. The roles alternate as the current alternates. Electricity is always flowing in a circuit, like your sink - it has a faucet and a drain. Water comes in, and goes out. We describe 220 V as being 2 "hots," but it is NOT like a sink with two faucets and no drain.

From the street, you get 2 hots and 1 ground. At your primary box, ground and neutral are connected. In all other boxes, they SHOULD be separated for safety (but not function).

In terms of FUNCTION AND THEORY (NOT CODE OR SAFETY) you could simply run a single wire of the appropriate gauge from the neutral side of your desired 120 V outlet to the ground/neutral bus of the primary box. You could connect one of the hots from your 220 V supply to the hot side of your desired 120 V outlet. You could run a ground wire from the ground screw of your desired 120 V outlet to the ground/neutral bus of your primary box. You would then have 120 V.

I am not suggesting that you do so - I am simply trying to explain the concepts by using an example. There is a difference between what WORKS and what is CONSIDERED SAFE. A lot of the codes are redundant safe guards. IMHO knowledge of codes is much more useful when we understand WHY the codes are in place, and exactly what risks we face if we violate a code.

Your wire sizes and breaker ratings must be proper, or you risk fire. But your house won't burn down if your hot wire is green.
 
I have never had a post get so many responses!!! I was an electronic tech at one time so I have a basic knowledge of how to wire thing up. I think I am just going to go to the trouble of running a 110V outlet to the bench and be done with it. Thanks to all of you who responded. And I think it is great how much collective knowledge is on this board.......

Allen
 
You must log in or register to reply here.
Back
Top