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Balanced load means no unbalanced currents, so the neutral current should be near zero.

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What does electrically balanced mean?

In a three phase system, if the current in all three phases are same, then it is a balanced system.


You get high voltage and burn your appliances due to neutral failure?

It would happen in case of 3phase domestic use where consumer side load balancing is not being done and there is loose connection in the neutral wire. Due to the unbalance and poor neutral, the system neutral will be shifted and un balanced voltages will be recorded in all the 3 phases of the house. The phase loaded with much utilities will indicate less voltage and other will have high voltage. Gadgets connected to this phase will be damaged.


How 3 phase unbalanced current flow through neutral?

Kirchoff's Current Law states that the signed sum of the currents entering a node is zero. If the neutral point is the node, then, in a balanced system, hot matches the other two hots, resulting in no current through neutral. Any imbalance, either due to neutral to hot current flow that is not balanced by the other two neutral to hot current flows, or due to ground fault, will result in a current flow on neutral, so that the sum of zero is maintained.When you think about this, remember that the law said "signed" and "entering". When you analyze a circuit, simply be consistent in your usage. For instance, in a balanced system, current entering the neutral node from one hot side is considered positive, and the current entering the neutral node from the other hot side is considered negative, i.e. it is leaving, not entering.This gets more complicated in three phase power, because now you have to consider phase angle, but the concept is exactly the same...If you are connected in wye, with a neutral, then the neutral conductor will have zero current on it only if the three phase hots have the same current on each. If you do vector analysis on this, adding up sin(x), sin(x+120), and sin(x+240), you get zero.The same thing happens when you are delta connected, without a neutral, but then the imbalance occurs out in the distribution system, beyond the service transformers, because the distribution system is generally a wye system.Ground fault will, of course, "change the rules", because you no longer have only four paths to that neutral point node. In fact, that is how ground fault current interrupters (GFCI's) work - they measure outbound current and compare it to inbound current - they must be equal and opposite, i.e. they cancel each other out - otherwise there is another path - a ground fault - and the device trips.


What is meant by neutral grounding reactor?

Neutral-earthing reactors or Neutral grounding reactors are connected between the neutral of a power system and earth to limit the line-to-earth current to a desired value under system earth fault conditions.


What happened if no neutral you can use a ground?

system will b damaged or destroyed in case of failures.............if we provide neutral d short ckt current passed through earth directly ,with out disturbing the system

Related Questions

Will the fifth harmonics will flow into neutral line in a 3phase balanced system?

for a balanced system ? no, cause 5th harmonics has purely negative sequence in balanced system, only zero sequences can flow. Unless the system is unbalanced, then only the 5th harmonics zero sequence component will flow in the neutral.


Why neutral cross section is half the phase in three phase cable while it has to carry current of summation of all phase..?

The current carried by the neutral of a three phase four wire system is the un balanced current. If the three phase system was completely balanced on all three phases there would be no need for a neutral, eg a three phase motor. This neutral current will be less that the phase current so a reduction in the neutral size is allowed.


What conductor does not carry current during normal operation?

In a three-phase power transmission system, the neutral conductor does not carry current during normal operation when the system is balanced. The neutral conductor is only used to provide a return path for unbalanced currents in the system and does not carry current when the system is operating under balanced conditions.


Why the neutral cable takes high current than the phase lines in three phase installation?

In a balanced three-phase system, the current in the neutral wire should ideally be minimal as the three phase conductors carry equal and opposite currents that cancel out in the neutral wire. However, if the loads are unbalanced, the neutral wire may have higher current due to the uneven distribution of power among the phases. This can happen when loads on each phase are different or when single-phase loads are connected between a phase and neutral, leading to increased neutral current.


Why 3phase 4 wire system neutral current is zero when balanced load conditionwhere same current flow through the phase and neutral also?

Because the voltage in the three live wires is 'phased' by one third of a cycle, or 120 degrees, and if the three currents have equal amplitude they add up to zero in the neutral. When one line peaks at +1 amp, let's say, the other two are both at -0.5 amps and there is nothing in the neutral. That state of affairs remains the same at all parts of the AC cycle.


Why is the neutral wire thinner in overhead 3-phase AC transmission line?

A smaller neutral wire in a three phase system can be used because it does not carry the full line current. It carries the unbalanced current of all three leg loads. This is one reason that three phase loads on a distribution panel should be equalized as much as possible to reduce the current on the neutral.


Can a 3 wire system create neutral voltages due to Harmonic distortion?

Yes, a 3 wire system can create neutral voltages due to harmonic distortion. Neutral voltages can also be caused by load imbalance between the two hots. It is normal for neutral to have a voltage differential relative to ground. Neutral is, after all, a current carrying conductor. In a well balanced system, however, there is little (theoretically zero) current in neutral.


What is line phase neutral?

Line, phase, neutral are terms used to describe the conductors in a three-phase system. The three live wires are called 'lines', and less correctly, 'phases'. Neutral is used for the fourth wire which in a balanced system carries no current.


How much current will flow in neutral line for three phase supply 100amps?

If all three legs of the system are balanced then zero amps will flow all the way up to 100 amps if only one leg of the three phase system is used. The neutral in a wye three phase system carries only the unbalanced current. This is why in services for a three phase four wire system you are allowed to reduce the size of the neutral conductor.


How you calculate voltage drops in a cable knowing resistance or impedance and line current in a 3phase system?

Ohm's Law - V = IR.


What is the difference between neutral point and earthing?

Earthing point is where conductor is directly connected to ground and its potential is always zero. Neutral is a return path in single phase system and in three phase system Neutral point will have zero potential if all the loads are balanced in the system. In un balanced three phase system even neutral point will have some potential


Why neutral line is 230 v in three phase ac supply?

3 phase supply can be configured in delta or Y. In delta configuration, think of the Greek letter delta (a triangle). The voltage is taken across two of the 'vertices' of the triangle. In Y configuration, the voltage is taken between a point and the 'neutral'. In a perfectly balanced system, no current would flow through the neutral line, but in the real world, no system is perfectly balanced. If you look at overhead power lines, the neutral line will be of a much smaller gauge wire than the 3 'hot' wires, because you can achieve close to a balanced load, therefore not much current will need to travel through the neutral.