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No. If you go to a motor supplier's web page such as Grainger's you can see for yourself. I looked up a 1HP good quality 115/230V motor: 115V @ 13.4A = 1541 watts 230V @ 6.7A = 1541 watts. The power consumed is the same no matter which voltage is used. This makes sense, since the watts do the work. To get the same 1HP from the motor, on either voltage, the watts (power consumed) must stay the same. Interestingly, in a perfect, lossless world, 1HP = 746 watts. So my example motor is less than50% efficient. Ouch. Figure out how to improve this efficiency a bunch and people will throw money at your feet! Assuming the two machines are doing the same work, the 240 volt will use slightly less power, or energy.

Here's why: To do the same work (btu) in the same time (btu/hr) they have to use the same amount of input power (watts). In fact watts and btu/hr are the same thing, "power", and there is a direct conversion from one to the other: 1000 watts = 3400 btu/hr. That's assuming 100% efficiency; real a/c units will of course need more power input than that.

Now in electricity, power = voltage x current. Since power input must be the same (since the output is the same), the 240 volt unit must be drawing half the current of the 120 volt. Power, the "electricity used", would be the same...

...almost. There is a wrinkle. The 240 volt unit is drawing less current. Now resistive losses are measured in power, and are calculated from P = current squared/R. i.e. cut the current in half (as the 240 volt unit does) and you cut the resistive losses to one fourth of what they were before.

So assuming all else is equal, resistive losses will be lower in the 240-volt unit. It will therefore be slightly more efficient, and so will use sligthly less power. The difference (mentioned above) will be much less than 1%, so for all practical purposes, the power consumed will be the same.

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How do you change a heater from 120 volts 3a to 240 volts 1.5 a?

the simplest solution is by connecting two 120v 3amps heater in series , the same can be used directly on 240v. However the current drawn will still be 3 amps & Not 1.5 amps. The heater output power will be double that of a single heater running on 120v. ( or equvalent to two heaters operating on 120v. supply ) A more expensive method is to use a stepdown transformer which can be powered on 240v & connect the heater on the transformer 120v side. this method will consume approx. 1.5 amps from the 240v supply.


WIll sump motor blow if I connect 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.


What countries use 240V?

Answer for USA, Canada and countries running a 60 Hertz supply service.The US runs 240V single phase in almost all residential applications.It just so happens that the 240V is center tapped to make 120V/240V split phase, but that is still a single phase application.For more information about the supply services in other countries, please see the answer to the Related Question shown below.


Can you run your neon sign of 120v 50hz 60hz 0.6a 7.5kv 30mA in an Australian 240v power outlet?

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


How can voltage increase to 240V when only 120V is coming from the breaker box?

This could occur if the 120V supply is split-phase, where two 120V lines are 180 degrees out of phase with each other. When measuring from one of these lines to the other, you would see 240V. This is a common setup in residential electrical systems in the United States.

Related Questions

You are building a new house and trying to decide between 120v and 240v which is better More practical?

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.


What happens if you plug a 120V appliance into a 240V outlet?

You will burn up your appliance!!!!!


How do you change a heater from 120 volts 3a to 240 volts 1.5 a?

the simplest solution is by connecting two 120v 3amps heater in series , the same can be used directly on 240v. However the current drawn will still be 3 amps & Not 1.5 amps. The heater output power will be double that of a single heater running on 120v. ( or equvalent to two heaters operating on 120v. supply ) A more expensive method is to use a stepdown transformer which can be powered on 240v & connect the heater on the transformer 120v side. this method will consume approx. 1.5 amps from the 240v supply.


WIll sump motor blow if I connect 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.


Can 240V washer run on 120V outlet?

No.


Why are you not getting 240v between the two hot wires?

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.


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.


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,,


What happens to a 120V 60HZ food dehydrator when connected to a 240V 50HZ supply using a voltage converter?

When a 120V 60Hz food dehydrator is connected to a 240V 50Hz supply using a voltage converter, the dehydrator may receive the correct voltage but could be affected by the frequency difference. The dehydrator is designed to operate at 60Hz, so using a 50Hz supply may cause it to run slower or inefficiently, potentially impacting drying performance and leading to overheating. Additionally, if the converter is not designed to handle the power requirements of the dehydrator, it could fail or damage the appliance.


Can I use 120v 10a 1250 w cable for projector 110-240v power in India?

You can use 120v 10a 125w cable projectors 110-240v power in India.


How to convert 120v to 240v for electrical appliances?

To convert 120v to 240v for electrical appliances, you can use a step-up transformer. This device increases the voltage from 120v to 240v, allowing you to safely power appliances that require the higher voltage. Make sure to follow all safety precautions and consult a professional if needed.


You have 120v photo flash lights - how do you use them with 240v in Oz?

Power adaptors are readily available that plug into Australia's 240v outlets, converting to 120v. Find them in travel, luggage and electronics stores.