You need the other phase, and a new outlet. Answer Completely new wiring and a different type receptacle. 10/3 cable will be required which isn't exactly cheap. For a short run though....maybe $20 for a scrap piece. Answer Not to mention a new breaker is needed.
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Given that the question states "an" appliance - just one not a house-full - you don't have to go through all that rigmarole. You could use just a step-up transformer plugged into the wall socket - but ensure the earth continuity (unless using double-insulated appliances), power rating, and obviously connector types, are suitable.
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The heading photograph, incidentally, is of the UK pattern, 230V (used to be 240V) a.c. "mains" plug and switched-socket. The large, un-shrouded pin is the earth and also opens a simple mechanical safety-gate within the socket to give the live and neutral pins access to their receptacles. The gate was introduced to guard against the risk of children poking things into sockets!
To operate a 240 volt small appliance from a 120 volt source, a step up transformer will be needed. The sizing of this transformer is dependent upon the load of the 240 volt appliance.
Once the load amperage is established on the secondary side of the transformer (240) using the Transformers ratio the primary side amperage can be established. This being a two to one ratio the primary side of the transformer will be double the amperage of the secondary.
For example a 1 amp load at 240 volts would need to draw an input of 2 amps at 120 volts. Notice how the transformer wattage stays in balance. W = A x V, 1 x 240 = 240 watts and 2 x 120 = 240 watts.
If the amperage of the primary side of the transformer (120) is above what a normal 15 amp wall receptacle can output then a larger 120 volt circuit will be needed.
The next step up is 20 amps with #12 wire used as the feeder conductor. Next is 30 amps with #10 wire used as the feeder conductor. This is about as far as you can go on a single breaker output of 120 volts.
You will burn up your appliance!!!!!
Not unless the appliance is rated to be used with the two different power supplies. The US uses 120v, 60 Hz if it plugs into a receptacle, and possibly 240v, 60Hz if it is hard wired. The UK uses 240v, 50Hz whether it plugs in or is hard wired. These two power systems are NOT compatible. You may use a US appliance in the UK, and vice versa, only if the appliance is dual rated, i.e. the appliance says 120v/60Hz AND 240v/50Hz on the nameplate. If the appliance only specifies one power supply, it can only be used on that power supply. If this is the case, you may be able to use a travel adapter to operate the appliance.
No, unless it's a gas range. An electric range requires 240V and 40A while a small appliance will be 120V and Max 15A.
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.
The voltage isn't a problem, you can run 220 from your house and use that to run a European appliance, the problem is whether the appliance is dependant on line HZ. European is 50HZ and US is 60HZ. If the appliance specifies 220/50HZ, it will probably give you trouble here. If it says 220V/50 or 60HZ
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.
No.
No. The neon sign is fed by a step-up transformer. Primary side 120V, secondary side 7500V. If you applied 240 to the primary side you would get 15000 volts on the neon tube. A flash over and then nothing. If you can find a transformer from 120V to 240V or 240V to 120V then you are good to go. Connect 240V to 240V side and you will get 120V out the other, connect the 120V side to the neon sign and you should have light. Transformer should be at least 100va. This will give you an output of .83 amps at 120V
For the most part, they cost about the same. For instance, if you look up a 120V, 2hp electric motor in a catalog, you will find it draws about 18A. 120V * 18A = 2160 watts. If you look up a 240V, 2hp motor, it will draw about 9A. 240V * 9A = 2160 watts. Watts are watts. Watts are what you pay for. It takes a certain amount of power to perform a particular task, irregardless of the voltage supply. You typically see larger loads, such as a dryer, range or AC unit fed from 240V. This is because the lower current draw permits you to run smaller wire, which is less expensive to install.
In the US, both 120v and 240v will be needed for your home, as different appliances need different voltages. Your TV needs 120V, while your electric dryer and stove will need a 120V/240V supply. If you have an electric water heater, or central AC unit, they will need a 240V supply.
Because they are "in-phase". In order to get 240v, you need two 120v Alternating Current lines that are 180° out of phase, that is, opposite phases. Only when one line is +120v and the other -120v will you see 240v between the wires.
Not a hard job or complicated but could be hazardous. Hire a professional.