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It's just the way three-phase works. The three live lines have a voltage of 230 v to neutral, let's say, and then the voltage between lines is 230 x sqrt(3). It happens because of the way the three voltages are timed, or phased, to peak in turn regularly through the AC cycle.

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Q: In three phase voltage calculation why we multiply line voltage by square root 3 not by 3?
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If in the three phase connection phase to phase voltage is 400v what will be the phase neutral voltage?

The formula to use is, phase voltage /1.73 = phase to neutral (ground) voltage.CommentThere is no such thing as a 'phase to phase', or 'phase to neutral' voltage. The correct terms are 'line to line' and 'line to neutral'. So the above answer should read: line voltage/1.73= line to neutral voltage = phase voltage.


What is 1.73 in load current calculation?

1.73 (the square-root of 3) is the ratio of line voltage to phase voltage in a star (wye) three-phase connection, and is the ratio of line to phase current ratio in a delta three-phase connection supplying a balanced load. In each case, it is derived from the phasor addition of two values displaced from each other by 120 electrical degrees.


What is the Phase to neutral voltage on a 400 volt 3 phase power supply?

The line-to-neutral (not 'phase-to-neutral'!) voltage on a 400V 3-Phase wye-connected system is 230V.Line voltage is the voltage as measured between any two (2) line conductors (hence its name!). Line voltage is often referred to as the 'line-to-line voltage'.Phase voltage is the voltage as measured between any single line and neutral. Phase voltage is often referred to as a 'line-to-neutral' voltage."400V" on a 400V 3-Phase wye-connected power supply indicates its line voltage. Line voltage in a wye system is always the phase voltage multiplied by the square-root of "3" (1.732) and reflects the vector sum of two individual phase voltages present in a three phase system.Thusly, if the line voltage is "400V", then the phase voltage is 400V divided by the square-root of "3" (1.732), which is 230V.Examples of this for North American power systems are 120/208V, 277/480V and 347/600V. Examples for other areas of the world are 220/380V, 230/400V and 240/415V.


Why do you have voltage to ground but not voltage phase to phase?

There is phase to phase voltage in 3 phase system.AnswerYou don't get voltage 'phase-to-phase'; it's 'line-to-line'!


How many amps can a 480 to 120 vac 3KVA transformer handle?

If the transformer is three phase the calculation is I = 30,000 / 1.73 E. If the transformer is single phase the calculation is I = 30,000 / E. (Where I = current and E = secondary voltage) It is important to note the voltage in the first formula is line to line (typically how it is specified in three phase power systems), and the second formula it is line to neutral.

Related questions

Why 1.732 value is include in three phase calculations?

It is the square root of 3. Multiply 1.732 to 120v. and you get 208. which, on a three phase system, is the voltage from line to ground.


What is the 11kv phase to earth voltage?

6350.8 volts AC rms. The phase to earth voltage is ( square root(3) ) x lower than the phase-phase voltage on a 3 phase system.


Why the voltage applied to each winding in a STAR configuration of three phase is reduced?

In a star configuration, often called "Y", the voltage across one winding is from a phase to ground. Phase to phase you have voltage across 2 windings. And at the risk of confusing you, the phase to phase voltage is not double the other because the windings are only 120 degrees out of phase and not 180 degrees. To calculate this you take the voltage of one winding, 120v for example, and multiply by the square root of 3, or about 1.732, and get 208v. Or you take 277v and get 480v.


What is the formula use for calculation voltage and current in star and delta?

Balanced Star (Wye) Connected Systems:Line Voltage = 1.732 x Phase VoltageLine Current = Phase CurrentBalanced Delta Connected Systems:Line Voltage = Phase VoltageLine Current = 1.732 x Phase Current


If in the three phase connection phase to phase voltage is 400v what will be the phase neutral voltage?

The formula to use is, phase voltage /1.73 = phase to neutral (ground) voltage.CommentThere is no such thing as a 'phase to phase', or 'phase to neutral' voltage. The correct terms are 'line to line' and 'line to neutral'. So the above answer should read: line voltage/1.73= line to neutral voltage = phase voltage.


What is voltage phase to phase 380 3 phase?

let me clear difference between phase voltage and line voltage. phase voltage is measure line to neutral and line voltage is measure line to line.there is correct answer that 380 volt is sum of multiply of square root 3 to phase voltage 220 volt.phase volt line volt220 volt x 1.732 = 381 volt230 volt x 1.732 = 400 volt240 volt x 1.732 = 415 voltM. Asif ALi


What is 1.73 in load current calculation?

1.73 (the square-root of 3) is the ratio of line voltage to phase voltage in a star (wye) three-phase connection, and is the ratio of line to phase current ratio in a delta three-phase connection supplying a balanced load. In each case, it is derived from the phasor addition of two values displaced from each other by 120 electrical degrees.


What is the Phase to neutral voltage on a 400 volt 3 phase power supply?

The line-to-neutral (not 'phase-to-neutral'!) voltage on a 400V 3-Phase wye-connected system is 230V.Line voltage is the voltage as measured between any two (2) line conductors (hence its name!). Line voltage is often referred to as the 'line-to-line voltage'.Phase voltage is the voltage as measured between any single line and neutral. Phase voltage is often referred to as a 'line-to-neutral' voltage."400V" on a 400V 3-Phase wye-connected power supply indicates its line voltage. Line voltage in a wye system is always the phase voltage multiplied by the square-root of "3" (1.732) and reflects the vector sum of two individual phase voltages present in a three phase system.Thusly, if the line voltage is "400V", then the phase voltage is 400V divided by the square-root of "3" (1.732), which is 230V.Examples of this for North American power systems are 120/208V, 277/480V and 347/600V. Examples for other areas of the world are 220/380V, 230/400V and 240/415V.


Why do you have voltage to ground but not voltage phase to phase?

There is phase to phase voltage in 3 phase system.AnswerYou don't get voltage 'phase-to-phase'; it's 'line-to-line'!


How do you calculate phase voltage of a three phase four wire system?

Phase voltage is determined by the wiring of transformer that serves the building. To test phase voltage use a volt meter and put one probe to ground and the other to each phase and observe the reading, this will give you a phase to ground voltage reading. Next test phase to phase (1 to 2, 1 to 3, and 2 to 3) to see if it's 208, 240, 277, or 480. Only licensed electricians should perform these tests. DAW


How many amps can a 480 to 120 vac 3KVA transformer handle?

If the transformer is three phase the calculation is I = 30,000 / 1.73 E. If the transformer is single phase the calculation is I = 30,000 / E. (Where I = current and E = secondary voltage) It is important to note the voltage in the first formula is line to line (typically how it is specified in three phase power systems), and the second formula it is line to neutral.


How is line voltage computed in a wye three phase cofiguration?

Line voltage equals phase voltage multiplied by the square root of three. a.k.a. E l = E p X 1.73 In a 3 phase 480v system the phase voltage is 277v. Therefore E l = 277 X 1.73 = 480v