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In a 4 wire, 220v AC circuit, each black wire carries 110v, the white serves as the return, or negative, and the copper is the ground.

So connect the white to the negative post of whatever your using (light or switch), and one of the black wires to the other for a 110V circuit.

If you're connecting a 110v two- strand wire to a 220v outlet, connect one wire to a black post and the other to the white post.

Make sure you have a neutral. Some times the white wire is the second hot and there is no neutral.

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โˆ™ 2015-07-15 19:09:11
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Q: How do you wire a 120V circuit off a 240V circuit?
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Related Questions

Can you tap into a 240V circuit to get 120V?

On a pure 240V circuit, no. There is no neutral. On a 240/120V circuit, yes. You have the needed neutral. Tapping 120volts off an existing 240volt branch circuit with a neutral is possible but is not a proper method. It does not comply with most electrical codes.

Can GFCI circuit breaker handle a 240V circuit with a 120V circuit sub-paneled off if it?

I don't know if you are trying to ask if you can run a 240V panel off a GFCI or run a 120 V sub panel off of a GFCI. Can you clarify please,,,Thanks

If you put a 60W 120V bulb in a 120V lamp that has a transformer for 240V and plug it into a 240V outlet will it work or blow the circuitry?

Off hand no but your explanations are not clear as to who is doing what to whom,,

How do you hook up a 3 wire water herter to 4 wire circut?

4 wire household wiring is black, red, (hot wires) white (neutral) and bare or green (ground wire). You say 3 wires. Is it 120v or 240v. If its 240v which is more common just use the two hots and the ground and cap off the neutral wire.

How do you wire a 1500W 240V flood light that has ground white and black wires?

the wires coming off double pole will give you 240 volts,110 each the black and white hook to these,doesn`t matter which way,ground to ground Ground is always ground, Black and white are your two "hots." You will need a dedicated circuit, you cannot run this off existing 120V wiring. A 15A 240V circuit should be more than sufficient. If this is a permanent instalation you can use 14/2 wire as you normally would, and wire it as you normally would with the exception of the 240V breaker. If you install switches, timers, etc. Make sure they are all rated for 240V. Remember, you can't just mix-and-match between 120 and 240V. 240 appliances will not run on 120 and 120 appliances will burn up on 240.

When going from 1-240v to 2-120v circuits do you need to replace the double pole breaker?

Yes, otherwise your double pole breaker will shut the other circuit off when one of them trips.

240V European and 120V US does one have an advantage over the other?

Generally 220v anything works easier or with less effort so can be cheaper to run. Appliances that run off 240V draw less current than 120V appliances so lighter wiring and fixtures can be used. However, 240V is more prone to arcing than 120V. Also, 240V is more likely to blow you away than 120V, whereas 120V is more likely to "grab" (Cause your muscles to involuntarily contract, i.e. making your hand grab a conductor) you. Also the US uses 120V because Edison originally used 100V. It was upped over the years to cope with demand. The US also has 240V in residential service for large appliances like ovens and dryers.

How can you convert a 240V clothes dryer to 120V?

You really cant do it because a 220 has a heating element in it to dry the clothes unlike gas that uses fire to dry the clothes and the 120 is to turn the drum.Your drier will keep poppin breakers which isn't good at all.Outlets and Power(110V outlets and 120V outlets are practically the same for this discussion. I will refer to them as 120V. Same with 220V/240V outlets.) By 110V outlet I'm assuming you mean a standard US 120V 15A outlet.This outlet can provide a maximum of 15A at 120V. This means the outlet can provide 1,800W of power. ( Volts x Amps = Watts ) This is the maximum amount of power this outlet can provide, no more. Also, this is assuming nothing else is drawing power off the circuit this outlet is on. If you try to pull 1800W from an outlet and plug anything else into this circuit, the breaker will blow.Your dryer is designed to run off a 30A 240V circuit. Let's say, for argument, it draws 24A at 240V. This means your appliance requires 5,760W of power to run correctly. This is 3.2 times the absolute maximum amount of power your 120V outlet can provide. There is no way you can run this appliance off this outlet. You have a larger problem here than the voltage difference.You can't, you need both a and b phases. You need to install an 240v receptacle.And don't upgrade to 240V by using the same wires!! Some complete idiots will try this and burn the neighborhood down.

Wiring circuit for 240V welder with 3 prong plug pulling 6-3 wire do you need to replace welder cable with a 4 lead cable-plug or can you avoid the white lead to wire a 3 prong outlet red-black-green?

It depends on the welder. If it doesn't need 120V you can just put a wire nut on the neutral and wire a 240V plug. If it needs 120/240V you need the 4 prong plug. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.If you do this work yourself, always turn off the powerat the breaker box/fuse panel BEFORE you attempt to do any work ANDalways use an electrician's test meter having metal-tipped probes(not a simple proximity voltage indicator)to insure the circuit is, in fact, de-energized.

What would cause light sockets to read 130V in a 240V system when the light switch is off?

More than likely, your 240V system has branches that supply a standard household 120V to things like lighting outlets. Most light bulbs in the US run on 120V so this is probably a convenience feature. Otherwise you would have to go to a specialty store and buy 240V bulbs.

What is use of fuse wire in electrical domestic circuit?

if there is a shrt circuit then the fuse wire will blow off to protect the domestic circuit

How would you wire a generator 120V 240V 4 prong twist-lock outlet to a 3 wire 1 hp 240V well pump?

First off you must make sure that your generator has overcurrent protect. This comes from article 445 in the NEC. Then size your wires accordingly. Then hook up your 2 hots, neutral, and ground, making sure you use wire that is listed for a wet location. Your pump will need a disconnect along with overcurrent protection.

How do I wire a 120V outlet from a 240V 3 wire service?

It is possible. For instance if you have a 30 amp 240 wiring to a appliance, you can tap a 120 out of it. You will need a small sub panel to do this. From there you will feed the the 120v and the 240v circuits. Check with your local codes to veriy.

How do you wire a water heater 240V black red green to 4 wire service black red white green?

Just cap off the white neutral wire. It is not used in 240v. Just hook up the black,red, and green

Why do furnaces use two phases of the home supply?

This is because furnaces are an enormous electrical load! The electric furnace for my 3 bedroom apartment is on a 60A 240V breaker. That means that for a medium sized apartment the furnace can use up to 14.4kW. Wow! Because the power draw is so high, the heater element runs at 240V instead of 120V. To draw that much power off 120V, the circuit would have to be rated to 120A. That is an enormous circuit, and is possibly enough to blow a main breaker if enough other appliances are on. By doubling the voltage a load you can halve the amount of current it draws. This allows for lighter wire, smaller control hardware, and is "healthier" for the house's electrical system.

Can you take a 240v 20a garage outlet number 12 with 4 wires and split it into two 120v circuits while still keeping the 240v outlet?

for USA, Canada and countries using similar 60Hz mains suppliesI'm not sure if the National Electrical Code is okay with it, but it is possible. Make sure you have a 20 Amp Double Pole breaker in the panel. Then, at the 240V outlet: You may need more room to accomodate all the wiring, so get a box extension, or if possible, upgrade to a larger box or use a junction box before the 240V outlet. Okay, Take the incoming neutral wire and connect it to the 2 120V circuits and to the 240V outlet. Connect the incoming red hot wire to a black 120V hot wire. Connect the 240V Black hot wire to the other 120V's hot wire. Connect all the ground wires together. Make sure that the box is grounded as well. Here's a simple formula for calculating the current you can use. Remember that the 120V circuits take current from one leg or the other, while the 240V Circuit takes from both. Since you have 2 120V 20A circuits, multiply the amps of the equipment you can use by 1. Now, multiply the 240V equipment's amps by 2. Add the values together. The value should be less than 32, and definitely not higher than 40. I recommend installing a 120/240V twistlok plug in the box. Then you can plug whatever you want into it. I made a nice distribution panel with 15A breakers for when I want 120V, and 240 can plug in directly. ( I use this method to power my Christmas lights. 2kW. :P)IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.If you do this work yourself, always turn off the powerat the breaker box/fuse panel BEFORE you attempt to do any work AND always use a meter or voltage indicator to insure the circuit is, in fact, de-energized.If there are only 3 wires entering the box, you can't legally do it. You can not use the same wire for a neutral and a protective ground. The 3 wires are the two hot phases and the protective ground.If there are 4 wires in the box, or if metal conduit provides the protective ground in addition to 3 wires, you can do it, provided the breaker is a double pole breaker. The white wire is the neutral, the bare one is the protective ground

If you have a 240V dryer and installed 30A breakers on both sides of the line reads 120 and 120 how do you get 240 and you have a receptacle that reads 30A 125250 and still does not work?

you do NOT put two 110v breakers in. you put 1 two pole breaker in. the panel is designed to give you 220v off one side OR the other side if you use a 2 pole breaker on one side or the other side. If you look at both 120V lines on an oscilloscope you will notice that they are both 120V to the neutral, but they are 180 degrees out of phase. This means that when one hot is at +120V the other is at -120V. So between the two you have 240V. If you put your meter across both hots you should see 240V. If you do not see 240V across both hots you (or an unlicenced electrician) has wired the outlet without using a proper 220V breaker. You do not see 240V because the hots are in phase, to the voltage differential is 0V, not 240V. 220V breakers cannot do this, unless forcebly installed in the wrong type panel. More than likely someone tried to wire it with 110V breakers.

In an electrical security light when turned on works as normal when turned of has 120 volts on the live and has 240 on neutral what would be the problem?

When light is turned off, you measure 120V at point B and 240V at point C. Since your reference point is A, then A to C is 240V and A to B is 120V. This iteration confirms point B ("120 volts on the live") is probably your neutral, and you are wired incorrectly.

Can you run 14 gauge wire off 12 wire to a receptical?

No, you can never mix wire sizes in a circuit.

Can you convert an existing 120V plug on an appliance to a 240V plug not speaking of a converter but actually changing the plug so there are no long term effects on the appliance?

If I understand your question, Can you run a 110 appliance off of a 220 volt outlet? You could by only using one leg of the 220. You may also consider changing the outlet. Put in a regular 110 outlet and capping off one leg of the 220 in the wall box. You still have a neutral and a ground to work with. I read this as the questioner doesn't want to modify the outlet. Check the voltage ratings on the device. Many electronic devices nowadays can havdle 120V or 240V as it is cheaper to manufacture one powersupply and sell it everywhere. If your device is rated for 240V, you can put a 240V plug on it. If it only says 120V, no dice. 240V will burn it up.

Would the black wire be line 1 on 240V line in?

On a 240 volt circuit both line wires are hot, so they may both be black, depending on the wire used. There is normally no neutral required unless you are also tapping off 120 volts between hot and neutral.

Can a cut cable wire cause a fire?

If by 'cable wire' you mean Coax cable for the TV, or Internet, then the answer is no. The power/voltages in the cable are way to low to produce a spark which is usually what triggers flame. If by 'cable wire' you mean a cable carrying an electrical service such as 120V or 240V, then, if the cable is damaged by an accidental or deliberate cut which causes a short circuit from a hot phase wire or wires to other wires in the cable - such as to other hot phase wires in a 3-phase circuit, a neutral or a ground wire - then the resulting heavy current could result in the cable becoming very hot and could cause it to catch on fire unless there was some overcurrent protection device to prevent that from happening. That is why fuses and/or circuit breakers should always be included in any electrical service wiring to cut off the supply of current before a fire can be caused by such damage.

When the main switch opf a house circuit is put off what does it disconnect?

Live wire and the neutral wire

Vauxhall astra vxr CD player wont turn off automatically when ignition is off?

Run the RED wire to a circuit controlled by the ignition switch. Only the yellow wire should run off the battery, or an "always hot" circuit.

What does a switch in a circuit do?

Allows you to break the Circuit or a portion of the circuit.A switch is a ON / OFF device which is used to control the current in an electric circuit .It is always connected to the live wire .