How can a 240V single-phase split ac work in the US which has a 120V 2-phase system?
Why does the US run at 120V when some of the world runs at 240V?
Technology, current at the time of US electrification, locked theUS into 110, then 120 volt outlets . Europe'selectrification came later, and proceeded in response to advancedtechnology. The US was too deep into the 110/120 voltinfrastructure to upgrade. The US has remained in this situationever si…nce. House voltage was first determined by Thomas Edison who set it foroptimal performance of his equipment. Additional Information: The United States distribution system actually provides a 240 voltresidential service in the form of two 120 volt conductors and aneutral conductor. You can see this if you look inside your breakerpanel. When a load is applied from either 120 volt conductor to theneutral (as is the case for typical receptacles, lights, and soforth) it is using 120 volts. However, when a load is applied from one 120 volt conductor to theother, without using the neutral, the voltage being used is the sumof 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 connectedwith only a two wire cable plus a safety ground wire. (For example240 volt base board heaters use this.) The only time a cable withthree wires plus safety ground is used is if 120/240 volts isneeded in the equipment. (For example kitchen ranges or washingmachines which have time clocks or programmers that require only a120 volt feed.) For systems outside the US, receptacles are 240 volts. Lowervoltages tend to be safer, which is why in the US, you arereceiving 240 volts at the home box and 120 at receptacles, insteadof the thousands of volts generated by the power plant. Power is transmitted over High Voltage cables - usually above 10KVolts. The power is then stepped down before it reaches consumers.Outlet power in the US is 120 volts, increased from 110 voltssometime around 1950. The US system theoretically could be made as good or better thanthe European system with no infrastructure change, exceptappliances and consumer structures themselves (collectively costing home owners billions). US housesget 240 volts at the panel. If wall outlets all were fed with 240Vyou'd have the lower current and higher power advantage of theEuropean system and it would be safer too, since each "hot" wouldstill be only 120V from ground (not 240V) which keeps the reducedshock hazard advantage. Of course it is still possible to touch thetwo hots. ===== The origin of the 120 volt standard dates back to the feud betweenGeorge Westinghouse and Thomas Edison. The first public electricityutilities were set up by Edison, whose concept was that there wouldbe a power station (Coal fired) at the end of every street,supplying low voltage DC. Westinghouse came up with the idea ofusing AC, which can be transmitted over long distances from a smallnumber of giant power stations. Edison worked to get the conceptbanned to protect his system by claiming that it would lead to theuse of dangerously high voltages. The result of this public debate was that the US opted for the lowvoltage, but using AC as Westinghouse recommended. (MORE)
If someone bought an electrical appliance in the US would it work in the UK given US appliances use 120V and UK use 240V?
I was a US Government employee. Me and my family were sent toEngland where we resided for 7 years. We shipped all our householdgoods with us including all our US electrical appliances. Oncethere, we purchased transformers which come in various wattageratings. The transformer actually converts the 22…0voltage down tothe required 120 volts for US products. Anything with a motor wouldonly be turning at 50 cycles a second vise the 60 cycles of UScurrent. This would only affect the playing speed of say a recordplayer (obselete now) but radios, toasters, coffee pots or anythingof 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 notnecissarily true, as the US has 120/240V service. You'd just need aspecial outlet for your 240V appliances..
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Some, but by no means all, electronic appliances have 110/240Vswitches to allow use on either system. (MORE)
Why does a 120V-240V dual voltage single phase table saw motor produce 4 times more torque at 240V than at 120V?
Answer .
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..
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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. (MORE)
Can an American 240V dual phase dryer be converted to work in Korea with 240V single phase power?
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 wi…re. 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. (MORE)
How do you change over so you can plug a 120V RV plug into a 240V single-phase twist-lock receptacle?
Answer .
Is the 220V plug 220V only or 110/220V? (The former will have 3 prongs and the former will have 4)\n.
\nIf your case is the latter just use the ground, neutral, and one of the hots. This will give you 120V single phase.\n.
\nIf the case is the former you can't get 110V off that plug.… (MORE)
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. More Not 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. (MORE)
How do you convert a 120V receptacle to a 240V receptacle for an air conditioner that uses 240V?
Answer .
\nA "110" volt outlet cannot be converted to a "230" volt outlet. A 230 volt outlet requires a new wire run to the outlet rated for the appliance you plan on plugging into it. Example an airconditioner that requires a 220 volt 20 amp circuit would have to have a 12/3 w/ground wire run t…o handle the load. The three wire are usually black,red,white. Black is for 1 120 volt line, red is for another 120 volt line and white is for neutral. On a standard 120 volt outlet there are 2 colored wires (black and whtie) and a bare ground. It's not an easy solution, but it is the only proper solution. (MORE)
How can you convert a 120V box to 240V for AC?
Answer .
It can't be "converted", you have to run a 220 line and have a 220 breaker and plug installed.
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. \n .
\n National Electrical Code definition, NFPA 70 2005 Article 100 I: Qualified Person. "One who has skills and knowled…ge related to the construction and operation of the electrical equipment and installations and has received safety training on the hazards involved." \n .
\n Performing any such operation without suitable qualification subjects your employer to action by OSHA. \nRead that as: "financial penalty" (MORE)
Will a 120V hardwire lighting fixture purchased in the US work safely in Germany 240V?
Answer .
No. It is not rated or designed for the higher voltage. Chances are it will catch fire.
Can you use 120V appliances on a 240V outlet?
Not advised .
Some appliances may work, but I imagine most would either blow a fuse or just burn out. Definately not advised unless you use a transformer. With the right transformer everything should work fine.
Will an HDTV made for 120V 60hz work in 240V 50hz if you use a voltage converter?
Answer Yes - but picture quality will be affected. Try also buyinga frequency convertor - maybe there is one on the market that doesboth. Check the TV Most modern TVs use a switching power supply asit is lighter and cheaper than a transformer. Switchers don't careabout frequency (at all) as they imm…ediatly rectify it to DC.Chances are it will run fine. Also, check the spec plate on theback of the TV. It may already handle 240V as it is cheaper tomanufacture one power supply that works worldwide than differentTVs for different countries. (Though the tuner in a TV may negatethis argument.) Answer Probably not, but this has nothing to do with the voltage.Televisions designed to operate at 240 V 50 Hz are likely designedfor European television systems which (except in France) use thePAL standard, whereas those designed to operate at 120 V 60 Hz arelikely designed for North American television systems which use theNTSC standard. Unless the television is multiple standard, theyneed to be used on the system for which they are designed, (MORE)
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 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 60H…Z (MORE)
Can you split a 240V wire to wire a 120V outlet?
Answer .
Yes you can, BUT IT IS DANGEROUS!!! You can use one side of the breaker to wire an outlet but if the outlet or the appliance you plug into the outlet shorts out, the breaker may not trip. Only half of the breaker will try to trip and the other half will not know to do the same therefore …you could over heat the circuits and cause a fire. NOT A GOOD IDEA..
That is a stupid answer, you cannot wire one side of a breaker. IT WILL NOT TRIP !!!! SO IT COULD CAUSE SOMEONE TO BE ELECTROCUTED. (MORE)
Can a 240V thermostat be operated using 120V to the themostat and them wired to a 120V heating element?
Answer .
a 240 volt thermostat (or any 240 volt switch) is generally a 2-pole switch which means it breaks both wires going to the load.
You can use it for 120 volt loads by using one of the two poles for the "hotleg" wire and just splice through the neutral wire.
this is a 2-pole switch (the …two blades move as one handle) line___.__ \___._ load line___.__ \___._ load.
The second pole goes unused and gives you a spare for the future (MORE)
Can you use a 120v switch for a 240v application?
Answer for USA, Canada and countries using similar 60Hz household electricity supplies .
This is not possible because a 120v switch disconnects one conductor while a 240v application requires that both hot conductors be disconnected simultaneously..
The proper solution is to use a double pole 24…0v switch of the correct size. It must have contacts which are rated to carry the appliance's starting and running currents (amps). A switch with under-sized contacts would be likely to get very warm - or even overheat - to such an extent that it might become a dangerous fire hazard..
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. . (MORE)
What are the 5Cs of credit?
5 C's of Credit refer to the factors that lenders of money evaluate to determine credit worthiness of a borrower. They are the following:.
1. Borrower's CHARACTER.
2. Borrower's CAPACITY to repay the loan.
3. COLLATERAL or security/guarantee for the obligation.
4. Borrower's CAPITAL (business ne…tworth) or downpayment for the loan.
5. Present and anticipated CONDITIONS of the borrower, collateral, business, and the industry or economy in general (MORE)
How do you use 120V equipment on 240V?
The short answer is: you can't..
The long answer is: just like using a flashlight bulb that has a voltage that is half the voltage of the battery, it will not work. It will take too much current, causing it to burn out and be useless.
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.
Will a DVD made for 120V 60Hz work in 240V 50Hz if you use a voltage converter?
Maybe....
most modern equipment will operate on 90V - 260V so it's worth checking before buying a voltage converter for it..
If the DVD player is 120V, that suggests that it is North American and will play NTSC standard discs. Using it on a 240V region means it is likely that it will be in a PAL z…one. THerefore, discs bought locally may not work because of regional codings, because of the difference between PAL and NTSC and because the display may not be able to handle NTSC..
Some DVD players will play any standard (NTSC or PAL) and some displays will also handle either standard. A handful of players do not have region codes either. It is worth a little more research before you assume that the DVD player will perform as you hope. (MORE)
Can 120V cloth iron be used in 240V?
The answer is No for an iron that was sold only for use in US, Canada or other countries using similar household AC power supplies..
Unless the iron has a switch on it, to allow it to be used safely in countries which use 220-240 volts as the standard household supply, a 120 Volt iron must only b…e used on the 120 Volt power supply that it was designed to use..
If it does not have a switch to convert its voltage, it is highly dangerous to try to use a 120 Volt iron on 240 volts. If a fuse or breaker did not trip to break the power supply the iron and/or its flex would overheat so much that they would probably catch on fire - not only would that ruin the iron, it would be dangerous to you and your home!.
If you change the iron's US-type 120 Volt plug to a US-type 240 volt plug, the results would be much more dangerous because a 240 Volt circuit has breakers designed to allow a high current draw - such as for a kitchen range or a clothes drier - and those breakers may not trip to cut off the current if you could just plug in a 120 Volt iron without first changing its plug. That is why the iron has a 120 Volt plug and not a 240 volt plug! (MORE)
Can you use 240v appliances on a 120v outlet?
There are 110 volts going to recepticles along the walls ect. These are for lamps, vaccuum cleaners, most things besides stoves, dryers, heating and cooling(most). But the only way to use your 110 volt outlet for a 220 is to combine 2 110 volt legs to make it 220 volt. Then you neeed to make sure yo…ur breaaker is capable of the increase. (MORE)
Can you operating 240v 60hz single phase electric kiln on 240v 50hz single phase power supply system?
If the kiln is strictly a resistance heating element, with no motor, then yes, it should work fine..
Warning : the opposite, that is running a 240V 50hz (European) appliance from US 240V 60hz mains is very dangerous and should not be attempted..
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.. (MORE)
How can you convert 240v to 120v for ac?
Use a step down transformer 240 primary to 120 secondary. You must know what the connected load (amps) is so that you don't overload the transformer. Small transformers are rated in VA.
Can 120v bulb work in a 240v socket?
Answer for USA, Canada and countries running a 60 Hz power supply service. .
Assuming this inquiry is a request for information rather than related to any practical application, here is the answer:.
It won't work for long. If it was a low-power bulb it would probably just go "pop" and be useles…s but if it was a high-power bulb it might even explode with a loud "bang", sending broken glass shards in all directions! .
So don't try to do it as an experiment because the result could be very dangerous. .
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 JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS. (MORE)
What does 5c stand for?
The Iphone 5C is Iphone 5Colorful 5c can also stand for thenumber 500 ("c" is the Roman numeral for 100) or for 5 degreesCelsius (centigrade) .
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"5c" can not stand for any Roman numerals forthree reasons. For a start you do not mix Arabic and Roman numeralslike that - it would be nonsensica…l. Secondly, the Roman for 100 is capital " C ", but thirdly, in the Romanscale, 5 is V, 50 is L and 500 is D. The ' C ' isalso capital for degrees Celsius / Centigrade. (MORE)
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 Edison connection. .
If you have a 240 volt single-phase supply, with two hot conductors, a neutral, and a ground wire, then yo…u 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. (MORE)
Can you split a 240v circuit into two 120v circuits?
yes, a 240 v circuit normally has 2 120 volt legs which are opposite phases and a neutral wire, there will be 120 volts between either hot wire and the neutral and 240 volts between the two hot wires.
What is the value of a stamp that says US Washington 5c?
To many variables to determine. Consult a catalog, available online or at your local library. In most cases the value is going to be pretty low, as Washington is a common subject for definitive stamps. But there are some with some good values to them!
What animal is on a 5c coin?
There are multiple animals on 5 cent coins depending on the country and time period such as the Buffalo on the US "buffalo nickel", the Beaver on the Canadian nickel, etc.
What is -5c plus 9 and how?
You can't tell a thing about -5c+9 until you know what 'c' is. And every time 'c' changes, -5c+9 changes.
How do you convert 240V single phase to 240V two phase?
You cannot. There is only single phase and three phase. Both come from the power company in wire distribution configurations. I believe in the Eastern united states there are still some two phase systems. If memory serves these systems have voltages that are 90 degrees apart. Sometimes three wires …are used to provide two phase service - the two phases and an oversized neutral wire that is used as the return for both phases. Since there is a phase shift involved to get two phases from one, you must have a phase shifting device to accomplish this. It is generally easier to get two/three phase service from your local utility company as opposed to try to generate it yourself. (MORE)
What is an AC single phase 2 wire system?
two wires coming off the secondary of the transformer ex. residential voltage of 120 volts each line, and one neutral wire, L1 to neutral is 120 volts, L2 to neutral is 120 volts, L1 to L2 is 240 volts. Answer A single-phase, two-wire, system comprises a line conductor and a neutral conductor.… In European countries, the line conductor for a residential supply is at a nominal potential of 230 V with respect to the neutral. In North America, a 'split phase' system is used for residential supplies; this is a single-phase, three-wire, system comprising two line conductors which and a neutral conductor. The nominal potential difference between the line conductor is 240 V, while the potential of each line conductor with respect to the neutral is 120 V. (MORE)
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.
How can you get a 240V 3-phase from 240V single-phase?
used only the two line of a 3-phase system. ex. used line 1 and line 2 only, or line 2 and line 3 or line 3 and line 1 to have a 240v single phase. The above answer has the question backwards. No, you can not obtain three phase supply from a single phase supply with out spending a bit of money. …If you are asking this to make a motor connection then that can be done. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start. (MORE)
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, whereas the system used in the US is a split-phase system in which one secondary phase winding of a distribution transformer is …centre-tapped and grounded (earthed). This provides 240 V between opposite ends of the phase winding, and 120 V from either end to the centre tap. (MORE)
What is 5c in milliliters?
5cc? cc means cubic centimetres which is equal to ml, so 5ml. if you mean cl, then that is equal to 50ml
How do you get 120v from a three phase system?
Three phase in the USA have two common voltages; either 277/480 or 120/208. if the panel the power is to be taken from is rated at 120/208 then a single pole breaker in the panel will supply 120 volts from any of the phases where as the circuit is complete through the neutral. although not commo…n to have, some of the three phase system having 120/208V set up could have the High phase B. that means that Phase B alone has a 208V phase to neutral; in other words a single pole breaker installed on phase B will supply 208V and not 120. Should the electrical system be 277/480V; then a step down transformer is required to produce the desired voltage. (MORE)
Which wire used single phase 240v 6.5kw load?
I = W/E. Amps = Watts/Volts = 6500/240 = 27 amps. A #10 copper conductor with an insulation factor of 90 degrees C is rated at 30 amps. If the load is continuous the conductor can only be loaded to 80% of its capacity. 30 x 80% = 24 amps which is too low for your load. Move to the next size wire whi…ch is a #8 which is rated at 40 amps x 80% = 32 amps. As long as no long distance runs are involved this wire size will work well. (MORE)
What is the answer for 5c equals -75?
The 'answer' is the number that 'c' must be, if 5c is really the same as -75. In order to find out what number that is, you could use 'algebra'. First, write the equation, so that you can look at it: 5c = -75 Now, use the law of algebra that says: "If equals are divided by equals, then… the quotients are equal". The left and right sides of your equation are equals. Divide them both by 5, and that law says that the quotients on both sides will be equal: c = -15 (MORE)
Can a 120v light bulb work in a 240v lamp?
If you mean that the lamp is rated for 240 volts then yes, a 120 volt bulb will operate in it if the lamp bases fit. If the 240 volt lamp is operating on 240 volts then no, a 120 volt lamp will not work in the fixture.
How many pixels does the iPhone 5c have?
The iPhone 5c is 640 x 1136 pixels. That is about 326 pixels persquare inch (ppi).
Can you use a 120v appliance with a 240v supply?
It depends on what the appliance is. Some smaller appliances have a dual voltage switch which allows you to adjust the appliance to the supply voltage. Look on the manufacture's nameplate label to see what they recommend as a working voltage. There it will also tell you whether the appliance can be …used on another voltage source. ==== Yes, you can. But it will fail ("burn out") almost immediately. If it's one that accepts either input voltage or if it has a little '120/240' switch on it, and you flip the little switch to the '240' position, then you're no longer talking about a "120v appliance". (MORE)
How can use 240v two phase for lighting?
Technically two-phase has not been used for about 100 years, but a240 v supply comes from a 240-v single-phase transformer. One ofthose with a centre-tap is often used to provide two 120 v suppliesas well as a 240 v supply, and that's a split-phase supply. Although 240 v bulbs are universal in some… countries like the UK,bulbs are normally made for 110-120 v in USA/Canada. (MORE)
What is minus 5c in Fahrenheit?
(-5) degrees Celsius = 23 degrees Fahrenheit. Formula: [°F] = [°C] à 9 â 5 + 32
Do skins for iPhone 5 lifeproof work for iPhone 5c lifeproof?
No, the skins won't fit. The iPhone 5 is 123.8 mm (4.87 in) high,58.6 mm (2.31 in) wide and 7.6 mm (0.30 in) high. The iPhone 5c is124.4 mm (4.90 in) high, 59.2 mm (2.33 in) wide and 8.97 mm (0.35in) thick.
How many inches is a iPhone 5c?
The screen is 4" big. The height is 4.9", width is 2.33" and thedepth is 0.35"
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 with a 240/240 v transformer with acentre-tapped secondary.
Why does my compass not work on my apple i phone 5c?
There may be stray magnetic fields in your house. Take it outside and run the calibration procedure.