How does 277 and 440 3 phase work and how is it different from 120 and 220 single phase?

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First, it's 277/480 and 120/240. But you're trying to relate what I call in the trade 'high voltage' 3 phase and 'low voltage' single phase.
Let's make it easier, with 'low voltages' only: you want to know the difference between 120/208 (3 phase) and 120/240 (split single phase).
First, look at your power source. Commercial services are often 3 phase, meaning you are using all 3 phases of generated AC in the building service. (look up AC generation for more information).
Residential services are really only using 1 of those 3 originally generated phases. Let's say a subdivision is made up of 30 houses, there will be approximately 10 houses on each phase from the power company to keep the load balanced.
On the ground somewhere (if underground service) or on a pole (overhead service) there is a transformer that converts single phase to split single phase. Some people incorrectly call this two phase power. Keep in mind you only have one phase from the power company's generator.
Split single phase enters a residence as two 120 volt conductors, and a neutral conductor. This is done by the pole or ground transformer's center tapped secondary winding. (Google this for more info) This center tap is actually where the neutral conductor is connected, and the two ends of the winding are where the 120v conductors come from.
A measurement from hot wire to hot wire in a residence produces about 240 volts, the sum of the two 120 volt legs. In fact, this is how your large electrical appliances operate. Your receptacles are connected to either 120v leg and a neutral.
Commercial services are actually simpler to explain. The power company produces 3 phases of power at very high voltages (to aid transmission over long distances), and those voltages are periodically stepped down lower the closer they get to a building's service entrance. As with the example earlier, there will be a ground mounted or pole mounted transformer that does a final step down before the wires enter the building.
When they do enter the building, they are the same 3 phases generated miles away at the power company. The difference is they aren't stepped down as low as residential services. Commercial services come in at 277 volts phase to ground, or 480 volts from phase to phase. Inside the building, there are more transformers that produce the 120 volt 'household' voltages for receptacles by stepping down even further.
Notice that in the residential example, the voltages are 120v phase to ground and 240 volts phase to phase. (Exactly double)
In the commercial example, the voltage is 277v phase to ground and 480v phase to phase, or 120v and 208v (depending on if you are talking high voltage or low). The multiplier here is not 2.0, it is 1.73, due to a different type of transformer used. I won't explain this in detail though. If you want to understand this, you need to do your homework.
Long winded, but if this question was easy to explain and understand, everyone could be an electrician overnight!

If you don't know what you are doing three phase will kill you dead in half a second, so don't mess with it, call a professional.

The 220V takes a phase from the 440V 3 phase, to neutral to give you single phase.
Say you had Red Yellow Blue, then take the Red phase (live) and a neutral and you will have half the 440V
To understand 277 3 phase and 440 3 phase you need a knowledge of how AC electricity actually works.

The two live power lines of single phase power in a house come from a single pole transformer. They are 180 degrees out of phase, due to the grounded center tap in the transformer winding.
The three phases are actually produced at the generator. They are sent down a set of three live wires and one neutral wire. Those are the wires you see on high tension power lines. There is always a multiple of three wires on big insulators, plus one ground wire. Three transformers are needed to step down the power for distribution, and three pole transformers feed the industry the three phases.
The three phases are 120 degrees apart from each other. This makes the sum of the currents in the three hot wires equal to zero. The currents flowing in one direction exactly equal the currents flowing in other direction in other hot wires. If the three phase system is properly loaded, no current flows through the neutral.
Three phases are the perfect source for a heavy motor. The three phases naturally provide a rotating magnetic field. A single phase motor needs a capacitor or shading coils to make the magnetic field rotate. And to reverse a three phase motor, a switch trades two of the phase wires.

The 120 degree difference in timing between the phases is why the voltages of two phases do not add to twice the voltage. Due to the phase difference, two 120 volt phases produce 208 volts, and two 277 volt phases produce 480 volts.
The 440 or 480 confusion exists because there is also 440/760 three phase power available.

ANSWER:You need to think of the relationship between the voltages in terms of vectors. Start at a point in the center of your paper and draw 3 lines originating from that point 120 degrees apart (Like a clock with one hand at the 12, another at the 4 and a third at the 7 - Approx). Each line should be the same length and end with an arrow pointing out. Now draw three dotted lines connecting the three arrow heads together. These dotted lines represent the potential (voltage) between each hot leg of the 3 phase system... So pick one (480V, 240, 208, [400 Europe]) and label your dotted lines with this voltage. The dot in the middle of your drawing = ground and we are interested what the voltage to ground is going to be.

Time for some trig! We know the angle between our 3 arrow lines is 120 degrees and we know the line opposite that angle = (Your voltage) mine is 208V. We are looking for the voltage of the adjacent line to my 120 degree angle, so we use the TAN function to give us the ratio between these two sides TAN of 120 degrees = -1.732. Since we don't care about the vector location, I can eliminate the "-" sign and call it 1.732. Since TAN = Opposite / Adjacent I can write the equation: 1.732 = 208 / Adjacent then 1.732(adjacent) = 208 then adjacent = 208 / 1.732 or adjacent = 120.09V. As you can see, 208 3phase was chosen for the availability of our common 120v single phase.
If you do the same calculation on 480V, you end up with 277V to ground. This is why you see so many light ballasts rated for 208/277V. If you run the calculation at 400V you get 240V to ground - the common European single phase voltage.
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What if 3 phase motor is single phase?

A three-phase motor will not start if one or two phases aren't connected. If while running one or two phases "drop out", it will continue to run for awhile, but will eventually burn out, unless connected to a motor saver.

How can you rewire 220 single phase to 110?

You need a neutral wire. Household 220 is two 110V hot wires that are in opposite phases, so the voltages add. Each of these hots will provide 110V when used with a neutral. It may be routed with the two hots, and it may not. If there isn't one there, it will need to be run from your breaker box.. ( Full Answer )

Can you convert 277 volts 2 phase to 240 volts single phase?

277 volts is the phase to neutral voltage on a 480V 3-phase system. There is really no such thing as 277V 2-phase.. Can you convert 277/480V 3-phase utility power to 120/240V single phase? Sure, but it will be expensive for any reasonable amount of power. You will need three transformers with 480:1 ( Full Answer )

What is the difference between single-phase and a 3-phase electrical supply?

Canada and US . To best explain this visualize the three primary line that you see on pole tops in industrial areas. The voltage between these three lines is about 14,400 volts. When you see a pod of three transformers mounted together they are combined into a three phase system. From each of the t ( Full Answer )

Can a 440 volt single phase device be made to run on 220 volt single phase?

Not directly. You could use a 220V - 440V transformer to boost the voltage up to 440. Be sure its rated for the proper KW. Check the nameplate on the device for the KW rating.. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS. . ( Full Answer )

What its the difference between 110 single phase and 220 single phase?

Answer for USA and Canada power supply service. . Electrical panel layout might explain where the two numbers come from on a single phase installation. On a electrical panel boards the wiring numbers go from left to right, top to bottom. There are 2 hot legs coming into the panel. L1 and L2. Brea ( Full Answer )

What is the difference in single phase and dual phase?

single phase means that there is only 1 live core in the cable (+) . so dual phase means there are 2 live cores in the cable. this is used to supply different parts of a device where needed. although three phase cable sometimes used to boost power to 400 v Further answer Actually it's not corr ( Full Answer )

How can you Step down 240volts 3 phase to 120 volts single phase?

Is there still 240V 3 phase around? Take 2 legs of the three phase 240V and use them as primary side of a 240 to 120 transformer. This will give you 120V single phase on the secondary side of the transformer. Make sure that you know the load current on the 120V side and size the transformer accordin ( Full Answer )

Will a welder with input voltage 208 230 single phase work on 220?

Yes, 220 and 240 volts are a nominal figure in the same voltage range. It is brought about by the power company, as they have a responsibility to keep voltages within a certain 10% range. The load will only notice a difference of 1% on the load current. eg. Wattage load of 2400. Amps = watts/volts. ( Full Answer )

How to convert 220 volt 3 phase from single phase?

With a single phase motor driving a 3 phase generator. It is possible to do it electronically, but that would more expensive and the more the power requirement is, the more expensive it would be.

How do you get 220 volt single phase from 480 volt 3 phase?

220 volt single phase from 480 volt 3 phase that one wire taken one phase and second wire connected in earth point. we get 220 v The above answer is incorrect, one phase from a three phase 480 volt system will give you 277 volts to ground. You must use a transformer to get the voltage you need. ( Full Answer )

What Difference between a single-phase power supply and a 3-phase power supply?

A single phase power supply has two "hot" legs or conductors which have a sine wave that are 180 degrees apart.. A three phase power supply has three "hot" conductors which have a sine wave that are 120 degrees apart.. You can thank Nicoli Tesla, whose birthday is today for the three phase or poly ( Full Answer )

What is the difference between a single phase and a 3 phase system?

for USA, Canada and other countries running a 60 Hz supply service. With three phase power you have three hot, or power, "legs" and one neutral, or grounded, "leg". With single phase power you have two hot, or power, "legs" and one neutral, or grounded, "leg". A three phase service costs mor ( Full Answer )

How do you tell the difference between a 3 phase and single phase motor?

To tell the difference between a single phase and a three phase motor... . A single phase motor will have two connections for power, hot and neutral. . A three phase motor will have three or four connections for power, hot/hot/hot for delta, or hot/hot/hot/neutral for wye. . There will also be a ( Full Answer )

How do you get single phase 440 from three phase 440?

You Don't. 440volt 3-phase is actually 480 volts, taking a single phase gives 277Volts single phase. To get single phase 440 you would use one leg of three phase 440/760 three phase power.

Why phase difference is 120?

Phase difference is 120 degrees because that is one third of 360 degrees. In a multi phase power system, you want each phase to divide a full cycle evenly. So, in a three phase system, each phase is delayed by one third of a cycle. A full cycle at 60 Hz is 16.7 mS, or 360 degrees. One third of tha ( Full Answer )

Can you get 220 three phase from 440 three phase?

To get three phase 220v from 440 you need to have a 440 to 220 three phase transformer installed. Cost is not prohibitive most depending on what KV is required are in the $500.00 range.

How many different single phase loads can connect to a 3 phase wye systsem?

As many single phase loads as is needed by the installation. The key to loading the three phase wye system is keeping the current equal in all three phases. As the neutral only carries the unbalanced current it is prudent to keep the current as low as possible by equalizing the loads on the phases.

Why is it stated - 3 phase 440 VAC when one phase voltage is 220 VAC?

In three-phase there are three live wires and a neutral. The voltage of a three-phase system is always quoted as the live-to-live voltage, and the voltage from one live wire to neutral is 57.7% of that. A 440 v 3-ph system has 254 volts between live and neutral. The question statement is not cor ( Full Answer )

How can you convert single phase 120 volt to 3 phase 480 volt?

You need an inverter or a motor-generator set. However, the cost of this will be quite high, and the efficiency will be quite low. Also, the available power will be rather low. The most cost-effective solution is to simply obtain 3 phase 480 volt power from your utility.

Can you get a 3 phase supply from single phase and how?

No, you cannot get a three phase supply directly from a single phase supply. Nowadays electronic inverter units can be bought that will do the job. For very low power loads the cost of such invertors is quite reasonable but for high power loads they are very expensive. For high-power industria ( Full Answer )

Can you turn a 3 phase into a 220?

Yes, 3 Phase, 415 Volts can be converted into 1 Ph, 240 Volts. Voltage between one of the phase (among 3 phase) and the Neutral is 239.6 Volts. How?: 415 V / root(3) = 239.6 Volts

How do you wire a roman weld transformer 120 kva 1 phase 440 volt from a 3 phase 480 delta-wye connection?

In a 480 volt wye connection you obtain two voltages, 277/480 volts. Any leg to grounded wye point will give you 277 volts. Between any of the legs to each other you will receive 480 volts. Any two legs of a three phase system is classified as single phase supply. From a 480 volt central distributio ( Full Answer )

Are there 3 phase 277 volt fixtures?

No because 277 volt is a single phase of 3 phase connected with the neutral. Of a 3phase 480V y system electrical service.

Can you run a 277 single phase heater on a 220 single phase?

Yes, you can but the wattage output rating of the heater will not be reached due to the lower applied voltage. For example if the heater is 5000 watts at 277 volts, the current is I = W/E 5000/277 = 18 amps. The resistance of the heater is R = W/I (squared) = 5000/18 x 18 (324) = 15.43 ohm ( Full Answer )

What is the difference between a single phase and a 3 phase circuit?

To answer this question in technical detail: a three-phase system is sourced from a three-phase alternator with a stator having three armature coils, each displaced from each other by 120 degrees. As the field rotor spins, it induces a voltage into each coil in sequence, making each voltage 120 elec ( Full Answer )

What is the mean of 220-440 connection of 3 phase motor?

Star 220 v and delta 400 i star 58 percent only voltage applied delta 400v applied Answer These figures do not represent three-phase, four-wire, system voltages, because if the line voltage were to be 440 V, then the phase voltage would be 254 V; or, if the phase voltage were to be 220 V, th ( Full Answer )

Why single phase are 240 and 3 phase are 440?

There is no such thing as a 440/240-V three-phase system. If 240 V is the phase voltage, then the line voltage will be 415 V. If 440 V is the line voltage, then the phase voltage will be 254 V.

Will 208 3 phase work on 220 3 phase?

Yes a 208 voltage motor will operate on 220 volts. You have to increase the motor overload protection by 10% of the motor's full load amperage to protect the motor.

How get 220 volt single phase from 380 volt 3 phase?

In a wye connection 220 volts is the line to neutral voltage of 380 volts. 380/1.73 = 220. The voltage of 220 volts will appear between L1 - N, L2 - N and L3 - N. All of these connections are classified as single phase connections.

How do you convert 3 phase to 220 v single phase?

Three phase is not converted to single phase. On a 240 volt three phase service 240 single phase can be taken from it. Any two legs from a three phase service is classed as single phase. L1 - L2 = 240 volts. The same is true with L2 - L3 = 240 volts and L3 - L1 = 240 volts.

What is a difference between 3 phase and single phase?

All electricity is generated, transmitted, and distributed as three-phase. Three-phase a.c. is generated by an alternator with, essentially, three armature coils that are physically displaced from each other by 120 degrees. Thus each of the three wires leaving that generator reaches its peak potent ( Full Answer )

Can a single phase be converted to a 3 phase?

A stand-alone 3-phase supply could be produced by a 3-phasegenerator shaft-driven by a mechanical power source which could bea single phase electric motor.

Why 3 phase 440 or 1 phase 230?

3-phase 400 v is 230 v single phase. That is a 3-phase 4-wiresystem, with three live wires and a neutral. The 400v is between any two live wires, while there is 230 v fromany live wire to neutral. With equal current drawn from each of the three phases, the systemis balanced and there is no current ( Full Answer )

Is 277 3 phase the same as 480 3 phase?

A 480 v 3-phase circuit has 277 v from neutral to each live line.So a 480 v 3-phase supply can provide three separate 277 v singlephase supplies.