# Why does a 120V-240V dual voltage single phase table saw motor produce 4 times more torque at 240V than at 120V?

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I believe it has to do with the windings in the motor. When wired to 120V, half the motor has a positive polarity and the other half has a negative polarity. Then as the current alternates (60 hertz AC) the polarity flips, the magnetic poles oppose each other and cause the motor to spin. I think in a 240v winding the motor is in quadrants instead of halves. So it would be like have 4 magnets opposing each other instead of two and you have double the voltage. Answer The calculation for electrical power (which is converted to torque) is voltage-squared divided by the resistance. If the voltage is doubled, the power is increase by 2-squared, or quadrupled. In reality, the torque produced will be slightly less than 4 times more (because some of the power is lost as heat), but it should be pretty close. -- The second answer is the best answer. The first answer could suggest several things, depending on how you read it. Nonetheless, they are all incorrect. The power calculation (in Watts) is really all you need to do. Voltage squared, divided by resistance. Resistance stays the same, so power quadruples when voltage doubles. If the motor spins at the same speed, then torque should effectively be linear with power, aside from the extra heat created in the components from the higher current.
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# How can a 240V single-phase split ac work in the US which has a 120V 2-phase system?

Note "2-phase" to describe US residential service is depricated nomenclature. US residential service is single phase because the two hot supply phases have 0 degrees of sepa

# How do you rewire a 120V or 240V motor running on 120V volts back to 240V?

I'm assume you're not working on a polyphasic system, so you have 2 hots and one neutral with 220VAC across the hots and 120VAC across either hot and neutral: The motor shoul

# Is 240V cheaper than 120V?

Answer . Cost is based on watts not voltage...pkazsr

# If you work in an industrial setting how do you make a 120V single phase line into a 240V single phase line?

Get an electrician . \nIf you work in an industrial setting and DON'T know how to do this, you should keep your hands off it. \nYou are not a suitably qualified individual.

# Is 120V or 240V more efficient?

Answer . If You Are Asking Which Will Cost Less. That Is Say A Motor ( Dual Voltage ) It Will Cast The Same To Operate On 110V As It Will 220 Volts. Reason You Only Pay Fo

# Single phase 4 pole Gen alt w 240V 60hz output no neutral. you check from each lead to ground and get 50-70V How do you get a neutral for connecting Gen to a standard breaker box having 240V and 120V?

Answer . \nNeutral is at the jumper that changes it from 120v to 240v. Two stator windings are used in series to make 240v; at that junction is (when wired in \nSeries)yo

# If you replaced a table saw motor from a 2 HP 120V 30A to a 3HP 240V 15A Is the existing 14ga wiring on the saw okay to use or do you need to upgrade to a heaver wire?

Answer . \nThat's right on the cusp. 15 amps is the maximum draw for 14 awg wire. I'd upgrade to 12 awg to be safe.. Answer . \nUnless you know exactly what you are d

# How can you convert US 120V or 240V circuit into a single-phase 240V circuit to use on a European appliance?

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 i

# What happens when you supply only 120V to a 240V motor?

Answer . it won't work properly.

# How do you rewire a 240V motor to 120V?

The linked site has just about any connection you might need. See related links below.

# What is cheaper to produce 120v or 240v?

You have to go right back to the source and find out how the electricity is produced. Coal fired, hydro, natural gas turbine. There is a specific cost for each method. For tra

# How do you get a split phase 120v 240v power supply from a single phase 240v supply for an American RV with a 50 amp service?

This is a common misconception. A standard 240 utility feed, common in the US, and a 120/240 feed are one in the same, the exact same thing. It is called (historically) an Edi

# Why does 3 phase motor have more torque than a single phase motor?

A simple way to look at it is to assume you were spinning a wheel by hand and you were spinning it harder once per revolution. If you applied a load of some sort to the wheel

# Can you take single phase of 120V with a hot wire and a neutral step up to 480v and then step down to 2 phases of 120V or do you have to input 2 phases of 120v to get 240V out?

Theoretically that can be done with transformers, but the poweravailable would still be limited by the circuit breaker on theoriginal 120 v supply.

# Can single phase 200v from japan use in US with two phase 120v 240V?

The US system is not a two-phase system; it's a split-phase system. But, to answer your question, probably not without damaging the Japanese device.

# How can a 240V single phase split ac work in the US which has a 120V 2 phase system?

The US does not use a two-phase system. In fact, two-phase systems are very rare, these days. A two-phase system is where the phase voltages are displaced by 90 degrees, whe

# How do you Convert 240V single phase to 240V and 120V single phases split ac system for testing purpose basically Indian system to US system?

It can't be done because the 240 v supply has a live and neutral. Asplit-phase 120/240 has a centre-tapped neutral so both outer wiresare live at 120 v. It can only be done wi