answersLogoWhite

0

for USA, Canada and countries running a 60 Hz power service.A service drop to a home is done with wire that is called triplex. This means that there are three wires twisted together that go from the service pole to the mast head on your home. This is called a three wire system. There are 2 hot legs and a neutral. The voltage between the hot leg (one) and the neutral is 120 Volts. The voltage between the hot leg (two) and the neutral is 120 Volts. The voltage between hot leg (one) and hot leg (two) is 240 volts. The single pole breaker is a safety device that connects to the (load, at 120 volts) and returns from the load back to the neutral. The load in most cases will be lights, plugs small appliances. The two pole breaker is a safety device that connects hot leg (one) to the (load, at 240 volts) and returns from the load back to the hot leg (two) at the two pole breaker. The loads in this case will be oven, range tops, hot water tank, clothes dryer, and in many homes baseboard heaters.

<<>>

In USA 240V comes into your home even though most of your equipment is 120V. I say most because your clothes dryer for one, if you have an electrically-heated one, most likely runs on 240V. The answer to your question is that 2 legs (power lines) come into your house. One leg is colored Black, the other is Red.

Each leg is 120V to common (ground). The voltage is AC (Alternating Current) so it is always going from +120V to -120V on each leg. But at opposite times, so that at some point in the cycle one leg is +120V while the other leg is -120V. And if you measure the voltage difference between +120V and -120V you get 240V.

The US wiring system works like this: to turn on your lights you switch into one leg, the current goes through your wiring to your lights and back to common. But your dryer switches into one leg and returns the current to the other leg. If you look in your breaker box you see breakers on both sides. Looking straight across, these breakers are on the same leg (L1). The next set down the panel are on the opposite leg (L2). Adjacent breakers all the way down the panel are on opposite legs. A two pole breaker spans these adjacent legs and that is how you arrive at 240 volts. Your dryer is connected to a two pole breaker that taps into both Black and Red legs.

<><><>

To accurately specify a voltage, you have to specify two points to measure, and the voltage is the difference between the two. If only one point is given it is usually implied that the second point is a grounded or 0 volt point. In the U.S., the three wires that enter most homes can be thought of as at +120V, -120V and 0V relative to ground. The 0V line is the "grounded" conductor, sometimes also called "neutral" and must be well connected to the earth where the wires enter the building (and no where else!) The +120 and -120 are actually different phases of an AC voltage wave. So by choosing which two points to connect to, a load can receive 120V or 240 V. Since there are two ways to get 120V, the breaker panel is usually set up to distribute the load between the two 120V phases.

<><><>

As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.

Before you do any work yourself,

on electrical circuits, equipment or appliances,

always use a test meter to ensure the circuit is, in fact, de-energized.

IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

.

User Avatar

Wiki User

9y ago

Still curious? Ask our experts.

Chat with our AI personalities

JudyJudy
Simplicity is my specialty.
Chat with Judy
RafaRafa
There's no fun in playing it safe. Why not try something a little unhinged?
Chat with Rafa
BlakeBlake
As your older brother, I've been where you are—maybe not exactly, but close enough.
Chat with Blake
More answers

To change 120V lines to 240V, you would need to install a step-up transformer. This transformer will increase the voltage from 120V to 240V. It's crucial to consult with a licensed electrician to ensure the conversion is done safely and in compliance with electrical codes.

User Avatar

AnswerBot

10mo ago
User Avatar

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.

User Avatar

Wiki User

17y ago
User Avatar

Yes, it is done with a step up transformer. The transformer is sized by the load that is connected to the secondary side of the transformer. Smaller control size Transformers are rated in VA (volt amps) and larger transformers are rated in KVA (kilovolt amps). VA is derived from amps times volts.

User Avatar

Wiki User

11y ago
User Avatar

A 240 volt breaker can be removed and replaced with 2 - 120 volt breakers.

The existing 240 volt breaker should not be used to supply 2 separate circuits.

User Avatar

Wiki User

9y ago
User Avatar

In simple words, NO!!! On the first day of Electricity 101 they tell you if you do not know what you are doing, DON'T DO IT!!!

User Avatar

Wiki User

19y ago
User Avatar

You DO use the old wire. You must not run new wire and outlets of proper load rating for the job. Doing anything else is dangerous.

User Avatar

Wiki User

15y ago
User Avatar

A far as I know, you can't. If a wire is used in a 120v circuit, the wire itself is only rated up to 15 amps, therefore it can't carry a full load without tripping the breaker.

User Avatar

Wiki User

16y ago
User Avatar

Absolutely NOT. The 240 outlet pin configuration would be different from the 120 volt pin configuration. They would physically not fit into each other.

User Avatar

Wiki User

9y ago
User Avatar

Add your answer:

Earn +20 pts
Q: How do you change 120V volt lines to 240V?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Continue Learning about Natural Sciences

How do you connect a 240V electric cooktop with four wires to the 120V services from the electric panel which is 2 wires?

It is not safe or recommended to connect a 240V electric cooktop to a 120V service. The cooktop requires 240V to operate properly. You would need to have a dedicated 240V circuit and receptacle installed to connect the cooktop safely.


Can you use 120V appliances on a 240V outlet?

No, 120V appliances are designed for use with a 120V outlet. Plugging them into a 240V outlet can cause damage to the appliance or pose a safety hazard. It is important to always match the voltage requirements of the appliance with the voltage supply.


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?

No, you cannot convert an appliance designed for 120V to operate safely at 240V by changing the plug alone. The internal components of the appliance need to be designed to handle the higher voltage to prevent damage and ensure safety. Modifying the plug without considering the appliance's design may lead to serious damage or pose a safety hazard.


Where is the problem if you have 240V on your 120V outlet and 120V on the neutral?

If you have 240V across the hot and neutral wires in a 120V outlet, it suggests there is a wiring issue with the outlet, possibly due to a short circuit. This is dangerous and can lead to electrical shocks or fires. It is best to immediately turn off power to the outlet and seek professional help to resolve the issue.


Can you wire a 120V stove fan to the 240V supply?

No, it is not safe to wire a 120V fan to a 240V power supply. Doing so can damage the fan and pose a fire hazard. It's important to use appliances with the correct voltage rating to ensure proper operation and safety.