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Why the current sum up to zero in neutral of a balanced load prove?
Wiki User
∙ 11y ago
Draw three phasors (vectors) at 120o with each other, with each the same length. Now, vectorially add those phasors graphically -you will see that they cancel.
Wiki User
∙ 12y ago
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Is there a current in star connected transformer in neutral side?
For a perfectly balanced load, with identical loads connected between each line conductor and the neutral conductor, there should be no neutral current. This is because the vector sum of three identical current, displaced by 120o, is zero.However, for an unbalanced load, there will always be a neutral current because the vector sum of the currents will not cancell.
In 3 phase wiring why neutral is thinner than that of phase?
As normally load distribution is done equally in all three phases, almost balanced current is drawn by load and current flow though neutral is very small when compared to the phase and hence difference in cable size is observed
Why is three-phase alternating current used for distribution systems?
Simply because it is cheaper. (You dont need the extra wire) However you can only use a 3 wire system if the load is a balanced load. If the load is not balanced you need the fourth wire (neutral/return) to take the out of balance current.
What if the fourth wire in a three phase is having impedance would the current in the neutral line remain to have a value of zero?
When the system is in balance, with three equal phase currents, there is no current in the neutral 4th wire and it is not needed. However if the load is unbalanced, the neutral is needed to maintain the star point at zero volts.So for example a street of houses fed by a 3-phase supply needs a neutral because the houses draw unequal currents from the different phase lines, although a large enough collection of houses would tend to balance itself out.If a three-pase system has equal currents the current in the neutral is zero. If two phases draw equal current but the third has no load, there is an equal current in the neutral, and if one phase draws current but the other two have no load, there is again an equal current in the neutral.ANOTHER ANSWERA three-phase, four-wire, system comprises three line conductors and a neutral conductor. If the load supplied by this system is balanced (i.e. the loads connected between each line and neutral are identical in all respects), then no current will flow in the neutral conductor regardless of its impedance. If the load is unbalanced, then a neutral current will flow in the neutral conductor. In other words, the impedance of the neutral conductor plays no part in whether or not there is a neutral current.
How do you balance the unbalanced load in 3 phase?
If the load is connected in wye (star) and it has a neutral, then the vectorial-difference of the phase currents will flow in the neutral and there will be no problem. On the other hand, if there is no neutral, then an unbalanced load would cause unbalanced phase voltages.
How much will neutral current be in a 3phase 4-wire y system with a balanced load?
Balanced load means no unbalanced currents, so the neutral current should be near zero.
How do you find neutral current in star connected circuit?
if it is balanced then neutral current is zero (!,e iR=iY=iB).AnswerFor both a balanced and an unbalanced load, the neutral current will be the phasor sum of the line currents.
Is there a current in star connected transformer in neutral side?
For a perfectly balanced load, with identical loads connected between each line conductor and the neutral conductor, there should be no neutral current. This is because the vector sum of three identical current, displaced by 120o, is zero.However, for an unbalanced load, there will always be a neutral current because the vector sum of the currents will not cancell.
Is the line is necessary for the balanced star- connected load?
I think you probably mean is a neutral conductor necessary for a balanced star-connected load? If this is what you mean, then the answer is no, it isn't, as the phasor-sum of the phase currents will equal zero. Often, though, it is difficult to achieve a balanced load, so a neutral is then necessary, as it is needed to provide a return path for the unbalanced current -without this neutral, the phase voltages would change and become unbalanced.
How do you resolve amperage on the neutral line?
By having a balanced load
In 3 phase wiring why neutral is thinner than that of phase?
As normally load distribution is done equally in all three phases, almost balanced current is drawn by load and current flow though neutral is very small when compared to the phase and hence difference in cable size is observed
Why is three-phase alternating current used for distribution systems?
Simply because it is cheaper. (You dont need the extra wire) However you can only use a 3 wire system if the load is a balanced load. If the load is not balanced you need the fourth wire (neutral/return) to take the out of balance current.
What if the fourth wire in a three phase is having impedance would the current in the neutral line remain to have a value of zero?
When the system is in balance, with three equal phase currents, there is no current in the neutral 4th wire and it is not needed. However if the load is unbalanced, the neutral is needed to maintain the star point at zero volts.So for example a street of houses fed by a 3-phase supply needs a neutral because the houses draw unequal currents from the different phase lines, although a large enough collection of houses would tend to balance itself out.If a three-pase system has equal currents the current in the neutral is zero. If two phases draw equal current but the third has no load, there is an equal current in the neutral, and if one phase draws current but the other two have no load, there is again an equal current in the neutral.ANOTHER ANSWERA three-phase, four-wire, system comprises three line conductors and a neutral conductor. If the load supplied by this system is balanced (i.e. the loads connected between each line and neutral are identical in all respects), then no current will flow in the neutral conductor regardless of its impedance. If the load is unbalanced, then a neutral current will flow in the neutral conductor. In other words, the impedance of the neutral conductor plays no part in whether or not there is a neutral current.
What is line voltage and line current in star connection define?
In star the voltage from line to neutral is 1/sqrt(3) times the nominal voltage, while the load current equals the line current. In delta the voltage between lines is the nominal voltage, while the load current is 1/sqrt(3) times the line current (for a balanced load). So a delta load needs 3 times the resistance compared to a star load of the same power.
What is a neutral wires' function?
To carry the unbalanced load current.
How do you balance the unbalanced load in 3 phase?
If the load is connected in wye (star) and it has a neutral, then the vectorial-difference of the phase currents will flow in the neutral and there will be no problem. On the other hand, if there is no neutral, then an unbalanced load would cause unbalanced phase voltages.
Does neutral wire carry voltage in a closed circuit?
The ground wire should carry no current at all, it is there in case of a short circuit to carry the (short circuit) current back to the breaker panel to trip the breaker. The neutral will carry the unbalanced load current between the 240 volt legs. e.g. L1 and N (neutral) 120 volts the load draws 8 amps. L2 and N (same neutral) 120 volts the load draws 12 amps. The difference between the two amperages is what the neutral will carry 12 - 8 = 4 amps.
