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Why does a 120V-240V dual voltage single phase table saw motor produce 4 times more torque at 240V than at 120V?
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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In the event of a city power cut can you use a single-phase 240V generator to connect across the two 120V phases supplying the house and would you still get 120V to neutral on each side?
Answer Yes you can BUT because you asked this question you should have a pro show you how to do it. Just to give you a worst case example, transformers work in both directions… so if you feed the "city" with 220v your neighbors will enjoy your power until your generator burns up. Maybe 2-3 seconds! Another thought Yes, IF you have a neutral connection at your generator. If you do not connect the neutral you will not have 110v from hot to neutral. This is because your house must be perfectly balanced across the neutral to have the correct voltage divider to split 220V into 110V. This is near impossible in a residential situation. You need the neutral for 110V. Also, buy a generator transfer panel if you plan to power your house off a generator. It's the law. MoreNot because it's the law, but if you don't have a transfer panel and you connect it directly to your panel you'll also be putting current to the lines coming into your house. This is real scary for the electricians that come out to repair the power. The (city) power is off and they don't expect to see (feel!) any on your end. You could end up electrocuting someone.
Answer That could only happen if the neutral wire (white) becomes disconnected at either the panel, the meter base or the transformer.
Electric stoves require 240 V typically. A gas stove may only require 120 V.
You don't. Electric devices like outlets have voltage and current ratings that should not be exceeded. Also, the 240V would have to be run from the main panel and may require …a different size wire depending on the current required.
Answer 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 c…ircuit with a neutral is possible but is not a proper method. It does not comply with most electrical codes.
Answer first off, the two 110v circuits would have to be from different bus bars in the breaker panel, one from the left bus and one from the right bus. if they …are both from the same bus you can't do it. if you count down from the top on one side of the breaker panel, every other single breaker space (they're numbered, 1,3,5,7... or 2,4,6,8...) is on the opposite bus, and the top breaker on each side is on the opposite bus. if you call the busses a and b then top to bottom on the left would be ababab... and top to bottom on the right would be bababa... if the two 110v circuits are from different busses, then the black (hot) wires from the two circuits would have 220v potential between them and the white wires (neutrals) would have no potential between them because they are connected to the same place back in the breaker panel, the neutral bus. if all you want is 220v, then the black wires would be all you need. it is a code violation to do this, however because an electrician or fireman has no way to know that he has to turn off two breakers to kill power to the one 220v device unless the two 110v breakers are together on the same side of the panel (ab or ba) and they are clearly marked on the legend as serving the same device.
Answer it won't work properly
No, the manufacturer specifies the voltage that the device has to operate on and this voltage has to be adhered to. If the question was "Is there a way to run a 120 volt produ…ct on 240 volts", then the following answer is correct. Answer Not directly, you will need a step down transformer between the outlet and the device.
Answer Cost is based on watts not voltage...pkazsr
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. Euro…pean 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
120 volts is used in Canada, 110 in the USA, 240 in the UK and Australia, 230 in Europe. 120 is less lethal than 240, but needs twice the amperage for a given task. An…swer North America uses a split-phase system, in which the 240-V secondary winding of a distribution transformer is centre-tapped and earthed (grounded) to providing the neutral connection. This provides a supply voltage of 240 V across the outer terminals of the secondary winding, and 120 V between either outer terminal and the neutral terminal. Thus residences are supplied with a dual-voltage system: 240 V for heavy appliances (e.g. ranges, dryers) and 120 V for normal loads (receptacles, lighting circuits). Most other countries use distribution transformers with a two-terminal secondary winding, which provide just one supply voltage: 240 V in some countries, and 230 V in the UK and mainland Europe.
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…son connection. If you have a 240 volt single-phase supply, with two hot conductors, a neutral, and a ground wire, then you already have 120/240 service. If you do not understand the terms above, then hire a qualified electrician to make the connection for you. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS. If you do this work yourself, always turn off the power at the breaker box/fuse panel BEFORE you attempt to do any work AND always use a meter or voltage indicator to insure the circuit is, in fact, de-energized.
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 separ…ation between their phases: therefore they are in phase. The two phases are pulled from 2 out of 3 corners on a 240v (line-to-line) 3-phase delta-primary transformer, usually out in the street. (Sometimes at your house if it's a big one). Basically all power is generated and transmitted as 3-phase. Usually around 415V 3-phase comes into the primary of the 3-phase transformer. (It could be delta- or wye-connected.) The secondary windings for all three phases will each have a center-tapped connection, and that's grounded at the panel. This is the neutral wire. All circuits in houses return via the "common" or "neutral" wire to this point, which happens to be grounded at the panel. Note: no neutral wires should be grounded anywhere else. The two "corners" are 240v relative to each other, and 120v each to the center tap. Each 240V circuit really is two hot wires plus a neutral, which is why it's often wrongly called two-phase when in fact it's just single-phase. For each 120V circuit in the house you're going to use one hot wire and one neutral wire. The neutral wire provides a return path for currents back to the generating station. In some installations, such as apartment blocks, the third leg of power would be at 208V with respect to the center tap. Another answer Just what does "220v single-phase split ac in the US which has a 110v 2-phase system" mean? The vast majority of electricity in the US is delivered as single phase or three phase. The only areas in the US that use 2-phase [for industrial and commercial purposes] are Philadelphia/South Jersey [where it is being phased out-no joke intended] and somewhere out west... It was one of the early poly-phase options pursued because of the natural magnetic differential between phases [makes motors spin without a capacitor] Most residences receive 220-240 volt single phase electricity with a grounded center-tapped neutral, the purpose being to limit voltage to ground to less than 150 volts from either "hot".
you could possibly design a fix for it but it would be a lot of trouble. the American dryer has internal components that run off 110v and that 110v is available from the three… wire 220v circuit in the typical usa residence. this is because of the third wire, the neutral. the Korean 220 would be 2 wire. you would have to go inside the dryer, add a 220/110 transformer and rewire the dryer so that the 110v loads come off that transformer. it would then no longer be ul listed and would have to be evaluated by the authority having jurisdiction in Korea and back here in the usa.
In The Byrds
Answer Most AC voltage supplies that need changed to another voltage, either up or down are changed with a transformer. To change 220 to 110 use …a transformer made for that purpose Make sure that the wattage rating is the proper size for the load(1500 watts etc.) properly fuse and ground the transformer Warning - voltages in this range are extremely dangerous make sure you know what you are doing
In general, no don't try it. The result will either be damage (e.g. overloaded motor burnout) to the appliance or a severe reduction (e.g. an electric heater giving off on…ly 1/4th its rated heat) in its performance.
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.