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Is it true that if you touch one phase line of a 3 phase system you will not be electrocuted?
Wiki User
∙ 14y ago
Not true.
This statement is true as long as you are insulated and isolated from any surrounding grounded material. By adhering to these conditions you do not provide any return path for the current to flow. On the odd occasion when an electrician has to work equipment "hot", it is only done with one hand while the other is secure in his pocket so as to not accidentally touch any of the surrounding grounded framework.
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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 REALLY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS.
Wiki User
∙ 14y ago
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What is the purpose of a phase conductor?
There is no such thing as a 'phase conductor'; the correct term is 'line conductor'. In a single-phase system, the line conductor is the energised conductor; in a three-phase system, there are three (energised) line conductors.
What is a line to line voltage?
In a 3 phase system, the voltage measured between any two phase is called line to line voltage.And the voltage measured between line to neutral is called phase to neutral (line to neutral) voltage.AnswerThere is no such thing as a 'phase-to-phase' or a 'phase-to-neutral' voltage. The correct terms are 'line-to-line' and 'line-to-neutral'.The voltage between any two line conductors is called a line voltage.In a three-phase, three-wire, system, the line voltage is numerically equal to the phase voltage.In a three-phase, four-wire, system, the voltage between any line conductor and the neutral conductor is called a phase voltage. The line voltage is 1.732 times larger than the phase voltage.
What is line voltage in star connection?
Phase to phase voltage is 1.732 (the square root of 3) times the phase to star point (neutral) line voltage.e.g. if the line voltage is 220Vphase voltage = 1.732x220 = 380V (approx)Additional AnswerYou might also like to know that the line voltage leads the phase voltage by 30 electrical degrees. And, incidentally, the correct expressions are 'line-to-line' not 'phase-to-phase', and 'line-to-neutral' not 'phase-to-neutral' (think about it, a line voltage is measured from the junctions between adjacent phases, so they cannot be 'phase to phase'!)
What are the uses of three phase transformer over single phase and their losses?
For a given load, a three-phase system requires around 75% of the volume of copper required by a corresponding single-phase system and, so, is more economical. A three-phase supply also delivers power more or less continuously, whereas a single-phase supply delivers power in pulses. Finally, three-phase motors are self-starting and physically smaller than single-phase machines of the same power rating.
How does a two-phase system differ from a three phase system?
A two-phase system is archaic and you are unlikely to find it in use anywhere these days, so it is mainly of historical interest. A two-phase, three-wire system, consists of two phase voltages, displaced from each other by 90 electrical degrees, and a phase voltage which is 1.414 x phase voltage.A three-phase system consists of three phase voltages which are displaced from each other by 120 electrical degrees. In the case of a three-phase, three-wire, system, the line voltages are numerically equal to the phase voltages; in the case of a three-phase, four-wire, system, the line voltages are 1.732 x phase voltage.
What is the purpose of a phase conductor?
There is no such thing as a 'phase conductor'; the correct term is 'line conductor'. In a single-phase system, the line conductor is the energised conductor; in a three-phase system, there are three (energised) line conductors.
Write dowen the relationshipbetween line and phase the 3phase system if voltageline and currentline are line value voltage power and current power are phase value?
A-for star connectionE(line)=1.73E(Phase)I(line)=I(Phase)&B-for delta connectionE(line)=E(Phase)I(line)=1.73I(Phase)
Why do birds not get sparks when flying near high-voltage lines?
If the bird is large enough to touch two different phase voltage lines or a grounded conductor ans a voltage line simultaneously it will be electrocuted. Just touching one line (and not a conductor leading to the ground) will not create a potential difference and so no current will flow.
What are the phase voltages if the line voltages are 100volts?
It depends on the type of three-phase system. If it's a three-wire system, then the phase voltage is numerically equal to the line voltage. If it's a four-wire system, then the phase voltage is numerically equal to the line voltage divided by 1.732 -in your example, this works out to be 5.77 V.
What is a line to line voltage?
In a 3 phase system, the voltage measured between any two phase is called line to line voltage.And the voltage measured between line to neutral is called phase to neutral (line to neutral) voltage.AnswerThere is no such thing as a 'phase-to-phase' or a 'phase-to-neutral' voltage. The correct terms are 'line-to-line' and 'line-to-neutral'.The voltage between any two line conductors is called a line voltage.In a three-phase, three-wire, system, the line voltage is numerically equal to the phase voltage.In a three-phase, four-wire, system, the voltage between any line conductor and the neutral conductor is called a phase voltage. The line voltage is 1.732 times larger than the phase voltage.
Which has the higher voltage - phase or line?
In a three phase three wire system, the phase voltage and line voltage are one in the same just different terminology. In a three phase four wire system, the line voltage is higher than the line to ground voltage. Line to ground is, line voltage divided by 1.73 (square root of three). For example 480volts /1.73 = 277 volts.AnswerIt depends upon the configuration of the three-phase system. For a delta (or mesh) connected 3-wire supply system, the line voltage is exactly the same as the phase voltage. For a wye (or star) connected 4-wire supply system, the line voltage is 1.732 (the square-root of 3) times the phase voltage.By way of explanation, for both wye and delta systems, phase voltages are measured across the windings of a three-phase transformer or across individual loads, whereas line voltages are measured between lines. For a wye-connected system, phase voltages can also be measured between any line and neutral.
What is line voltage in star connection?
Phase to phase voltage is 1.732 (the square root of 3) times the phase to star point (neutral) line voltage.e.g. if the line voltage is 220Vphase voltage = 1.732x220 = 380V (approx)Additional AnswerYou might also like to know that the line voltage leads the phase voltage by 30 electrical degrees. And, incidentally, the correct expressions are 'line-to-line' not 'phase-to-phase', and 'line-to-neutral' not 'phase-to-neutral' (think about it, a line voltage is measured from the junctions between adjacent phases, so they cannot be 'phase to phase'!)
What are the uses of three phase transformer over single phase and their losses?
For a given load, a three-phase system requires around 75% of the volume of copper required by a corresponding single-phase system and, so, is more economical. A three-phase supply also delivers power more or less continuously, whereas a single-phase supply delivers power in pulses. Finally, three-phase motors are self-starting and physically smaller than single-phase machines of the same power rating.
How does a two-phase system differ from a three phase system?
A two-phase system is archaic and you are unlikely to find it in use anywhere these days, so it is mainly of historical interest. A two-phase, three-wire system, consists of two phase voltages, displaced from each other by 90 electrical degrees, and a phase voltage which is 1.414 x phase voltage.A three-phase system consists of three phase voltages which are displaced from each other by 120 electrical degrees. In the case of a three-phase, three-wire, system, the line voltages are numerically equal to the phase voltages; in the case of a three-phase, four-wire, system, the line voltages are 1.732 x phase voltage.
How do you convert 3phase connection to 2 phase?
Any two legs of a three phase system can be classed as a single phase supply.Alternative AnswerAs the above answer points out, connecting a load between any two line conductors of a three-phase supply will give you a single-phase load. But you must, of course, take into account the voltage rating of the load you wish to connect.In Europe, three-phase low-voltage distribution is normally by means of a four-wire system, comprising three line conductors and a neutral conductor, operating at 400 V (line-to-line) and 230 V (line-to-neutral).Your single-phase load's voltage rating must, of course, match either the single-phase supply's line-to-line or line-to-neutral voltages. In Europe, most single-phase loads are rated at 230 V so, for a residential three-phase, four-wire system, it is usual to obtain a single-phase supply by connecting the load between any one of the line conductors and the neutral conductor.But, if you have a non-standard, 400-V single-phase load, then connecting that load between any two line conductors will also give you a single-phase supply.
What is phase line?
In a three phase system the term line refers to any one the three legs that are used in the system. The termination points are L1, L2 and L3. The voltages between any three legs will be the line voltage.
Is transmission line voltage phase to phase?
Yes usually it would be phase to phase voltage because most transmission lines are set up in a delta configuration. This means that there is no neutral conductor to use as a reference. So any voltage would be measured with reference to another phase.CommentLet's get the terminology correct. The voltages between the three 'hot' lines of a three-phase, three- or four-wire, system are called 'line voltages' even though, in the case of a delta-connected system, they are numerically-equal to the corresponding phase voltages. Therefore, we call the conductors 'line conductors', not 'phase conductors'.There is simply no such thing as a 'phase-to-phase' voltage. Just think about it; you can only measure a voltage acrossan individual phase, so how can you possible measure a voltage 'phase-to-phase' -I mean, where would you place a voltmeter to do that?For a delta system, the line voltage (or line-to-line) voltage is numerically equal to the phase voltage (notphase-to-phase). For a star (or 'wye') system, the line voltage is equal to 1.73 x the phase voltage.
