Technology, current at the time of US electrification, locked the US into 110, then 120 volt outlets. Europe's electrification came later, and proceeded in response to advanced technology. The US was too deep into the 110/120 volt infrastructure to upgrade. The US has remained in this situation ever since.
House voltage was first determined by Thomas Edison who set it for optimal performance of his equipment.
Additional Information:
The United States distribution system actually provides a 240 volt residential service in the form of two 120 volt conductors and a neutral conductor. You can see this if you look inside your breaker panel. When a load is applied from either 120 volt conductor to the neutral (as is the case for typical receptacles, lights, and so forth) it is using 120 volts.
However, when a load is applied from one 120 volt conductor to the other, without using the neutral, the voltage being used is the sum of both 120 volt conductors (240 volts). This is the case for many water heaters, air conditioners, electric furnaces, clothes dryers, and so forth.
So equipment that is connected to strictly 240 volts is connected with only a two wire cable plus a safety ground wire. (For example 240 volt base board heaters use this.) The only time a cable with three wires plus safety ground is used is if 120/240 volts is needed in the equipment. (For example kitchen ranges or washing machines which have time clocks or programmers that require only a 120 volt feed.)
For systems outside the US, receptacles are 240 volts. Lower voltages tend to be safer, which is why in the US, you are receiving 240 volts at the home box and 120 at receptacles, instead of the thousands of volts generated by the power plant.
Power is transmitted over High Voltage cables - usually above 10K Volts. The power is then stepped down before it reaches consumers. Outlet power in the US is 120 volts, increased from 110 volts sometime around 1950.
The US system theoretically could be made as good or better than the European system with no infrastructure change, except appliances and consumer structuresthemselves (collectively costing home owners billions). US houses get 240 volts at the panel. If wall outlets all were fed with 240V you'd have the lower current and higher power advantage of the European system and it would be safer too, since each "hot" would still be only 120V from ground (not 240V) which keeps the reduced shock hazard advantage. Of course it is still possible to touch the two hots.
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The origin of the 120 volt standard dates back to the feud between George Westinghouse and Thomas Edison. The first public electricity utilities were set up by Edison, whose concept was that there would be a power station (Coal fired) at the end of every street, supplying low voltage DC. Westinghouse came up with the idea of using AC, which can be transmitted over long distances from a small number of giant power stations. Edison worked to get the concept banned to protect his system by claiming that it would lead to the use of dangerously high voltages.
The result of this public debate was that the US opted for the low voltage, but using AC as Westinghouse recommended.
Actually, I have seen this in a respected electronics magazine (Elektor) quite some time ago: A diode (selected to be capable to handle the amps, the voltage and the heat from the bulb - if placed inside the lighting fixture) is used to "cut off" one half of the AC sine wave and thus sending pulses of 120V to an incandescent light bulb, simulating a simple dimming device. The proposal was meant to run 240V bulbs at 50% of their brightness but I am pretty certain this concept can be used to run 120V bulbs from 240V power. One other way of connecting 120V bulbs to 240V would be to connect two 120V bulbs OF THE SAME WATTAGE in SERIES, so the two bulbs form their own voltage divider. Not sure what happens if one bulb burns out - I would expect the other one to blow too, as a dying light bulb represents zero Ohms (plasma/arcing) for a few milliseconds before it goes dark forever.
I have never come across this terminology in the electrical trade. The letter L is a symbol used to express inductance. The unit of measure is a "Henry"In some documentation the system voltage legs are referred to a A, B, and C. In the electrical trade the letter L is used with a reference number behind it. For example L1, L2 and L3 represent the three legs of a three phase system. Incorporating the letter N into the system would give you a representation of a three phase four wire system where you would obtain a voltage from each leg to the grounded neutral. The voltage from any of the three legs to neutral would be, leg to leg voltage divided by 1.73. This would give you the leg to neutral voltage. For example 480 volts / 1.73 = 277 volts or 600 volts /1.73 = 347 volts.
It depends on the local utility power company and the the neighborhood transformer taps used. It also depends on how far away the transformer is from the house. There is a voltage drop depending on the size and length of wire. It sometimes is 120v, 125v, 130v or anywhere in between. It doesn't make much difference.
A resistance furnace runs on electricity so it will be some type of electrical transformer.
I was a US Government employee. Me and my family were sent to England where we resided for 7 years. We shipped all our household goods with us including all our US electrical appliances. Once there, we purchased transformers which come in various wattage ratings. The transformer actually converts the 220voltage down to the required 120 volts for US products. Anything with a motor would only be turning at 50 cycles a second vise the 60 cycles of US current. This would only affect the playing speed of say a record player (obselete now) but radios, toasters, coffee pots or anything of that nature would work fine. Hope this has helped. You need a transformer, as mentioned above. Note that for running UK appliances in the US that is not necissarily true, as the US has 120/240V service. You'd just need a special outlet for your 240V appliances. +++ Some, but by no means all, electronic appliances have 110/240V switches to allow use on either system.
Do you mean Single Phase? This is what supplies American homes and some commercial buildings. It is 120V/240V.
It may not blow, but it will turn twice as fast and burn out very quickly. It is meant for 110 only. Check the sump pump. Some of them can be wired either 120v or 240v. If yours is like that, just wire the motor for 240v and plug it in.
120v and 240v cords usually have different end configurations and will not plug into the different recepticles. However, if you changed the plug end, and the cord has the proper size rating, then yes, you could use the same cord. But, it also depends on the cord too. Most 120v cords only have three wires in them. One "hot one "neutral" and one "ground" wire. A 240v cord would have FOUR wires, two "hot" wires, one neutral wire, and one ground wire. Therefore, if you changed the voltage from 120v to 240 using a 3 wire cord, you'd not have a ground wire and that could be VERY dangerous. Note that occasionally a 240v device (e.g. some motors) will only need three wires (red,black,green, no neutral) and can be wired with a 120v cord if the cord is rated for 240v.
For USA, Canada and countries running a 60 Hz supply service.1) An outlet for 240V is totally different from a regular 120V outlet. 2) The wiring for 240V is also much heavier than for 120V.3) The double pole circuit breaker necessary for 240V is different to the single pole breaker used for 120V.4) Anyway it is not clear why you would want to try to change a 240V outlet to a 120V type?5) If you could log in and add some more details below here so we knew your reasoning for wanting this change to take place, someone may be able to assist you much further.The reason why I need to do this is because there is only one 3-prong 240V outlet in the water heater closet feeding an inline water heater and I want to install an instant hot water recycling system which runs on 120v I so need the extra power outlet.If you want to keep the existing 240V water heater then you cannot add another outlet to the circuit, not even a 240V one, let alone a 120V one!The wiring and its circuit breaker is only rated to carry the current for one water heater and nothing else. If you add another appliance to the circuit you risk causing a house fire: the breaker may buzz but not trip so that the wiring gets hotter and hotter until something catches on fire!So, if you are planning to buy a new hot water recycling system it surely deserves to be installed safely and correctly?So why not, for your instant hot water recycling system, have a licensed electrician install a separate 120V circuit with the correct breaker, the correct-sized cable and the correct outlet near to the existing 240V outlet?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 JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
NO. Don't try it. Some are designed to work on either, some aren't. If it won't work on 120v, it won't work on 240v.
You can't "convert" a 120V receptacle into a 240V receptacle.A proper new 240V branch circuit complete with correctly sized circuit breakers, wiring and socket outlet is required.For more information see the Related Question shown below.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 JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
Actually, I have seen this in a respected electronics magazine (Elektor) quite some time ago: A diode (selected to be capable to handle the amps, the voltage and the heat from the bulb - if placed inside the lighting fixture) is used to "cut off" one half of the AC sine wave and thus sending pulses of 120V to an incandescent light bulb, simulating a simple dimming device. The proposal was meant to run 240V bulbs at 50% of their brightness but I am pretty certain this concept can be used to run 120V bulbs from 240V power. One other way of connecting 120V bulbs to 240V would be to connect two 120V bulbs OF THE SAME WATTAGE in SERIES, so the two bulbs form their own voltage divider. Not sure what happens if one bulb burns out - I would expect the other one to blow too, as a dying light bulb represents zero Ohms (plasma/arcing) for a few milliseconds before it goes dark forever.
In some parts of the world, an 1875 watt hair dryer can and does use 220 volts from a 220 volt outlet?
If you mean - can you run a 220v device on 120v where the 220v device needs that level of voltage to operate correctly then the answer is no. Even disregarding the frequency difference which some devices aren't affected by, the voltage difference is too great. Some devices these days, such as phone chargers, laptop power supply units etc will run happily on a voltage range from 100v up to 240v (read the label first) but they are the exception. The question is somewhat ambiguous and needs more information.
Hire an electrician to install for you a 240 line. I agree with Tim. You need a dedicated circuit for a dryer. The wiring is larger and you cannot use the 12/2 wiring that is already there. You need a home run from the dryer to the electricl panel. You need an electrican.
110V and 120V are essentially the same thing--don't worry about that. 50 Hz vs. 60 Hz is more important, for some devices. North America is 60 Hz; much of the rest of the world is 50 Hz.
NO! Check the rating on the device and if it says 120V only don't ever dare plug into 240V. Depending on the appliance the results will either be lots of sparks, large flashes or other undesirable side effects.Another engineer's opinionThat answer above is for USA, Canada and other countries which use the 60Hz electrical service standard, for appliances which were designed to run only on that voltage and nothing higher.If this question is asking about using 110V to 120V appliances plugged into sockets elsewhere in the world which use the 50Hz 230 to 240V electrical service standard - such as Europe, Australia and many other countries - then the answer is not necessarily NO.Providing you use the correct type of plug adapter to suit the sockets in each country you visit, if the appliance was designed to run on 110V to 240V services, then the answer is YES.There are many personal electrical and electronic appliances which were designed to run on voltages within a wide range such as 110 to 240 volts! Just a few examples are: electric razors, hair dryers, battery chargers for digital cameras, mp3 players, etc.IMPORTANT SAFETY NOTESuch multi-voltage small appliances should never be used on the 220 to 240 volt outlets in USA or Canada or other countries which use the 60Hz electrical service standard.Such 220 to 240V outlets are intended for use only by large appliances, such as water heaters, clothes washing machines and dryers, cooking ranges, etc. Such 220 to 240V outlets are quite different in size to 110 to 120V outlets anyway and no adapters should ever be used to try to use those kinds of portable small appliances on 220 to 240V 60Hz.It may be illegal to do so in some countries or states because:correct size lower voltage 110 to 120V outlets are available to be used andif one of those small appliances gets a fault, the circuit breakers protecting a 220 to 240V branch circuit probably won't trip to break the current, which could result in enough flames to start a house fire.