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What happens if you change phase and neutral in 3 phase circuit?
Wiki User
∙ 10y ago
breaker will trip, motor will smoke, a loud noise and possible arc if 480 volts or motor would run counter clockwise if crossed at motor j box or at the disconnect. always make sure junction boxes are made up properly before turning on power if over 100'
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LOL, but not a great answer. If phases get reversed in a three phase system, the only devices that would be directly effected are the connected motors. There is no effect to three phase resistive loads nor single phase loads connected off of the three phase service. There will be no smoke, loud noises or arcing. Most industrial and commercial installations have phase reversal instrumentation connected to the system that sense the incoming lines for just such a condition. This instrumentation is connected to a shunt trip breaker that will disconnect the service from the grid. The utility companies are very careful about re installing the proper phasing of downed lines after a storm and before energizing a new line installation.
Wiki User
∙ 14y ago
Wiki User
∙ 12y agoany motors will opperate in the oposite direction
AnswerYou need to make your question more clear. Do you really mean 'reverse a phase' or do you main swap two lines?
Wiki User
∙ 10y agoIf the load is resistive there would be no effect. If the load was inductive, for example a three phase motor, the motor would rotate in the opposite direction. Phase reversal of a motor that turned in a clockwise rotation when connected ABC would change, after phase reversal ACB the motor would turn in a counter clockwise rotation.
On a motor reversing the sequence would make the motor run in reverse.
Wiki User
∙ 12y agoThe 3-phase motors will change direction of rotation.
Wiki User
∙ 9y agoChange any two wires.
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How does a phase leg connect to a neutral in an electrical circuit?
A phase leg connects to the neutral through the connected load.
In a 240 volt single phase circuit A phase is 4000 watts B phase is 7000 watts what is the neutral load?
Question is incorrect. in a 240 Volt single phase circuit, how can you have A phase and B phase?
What will happen if a phase and neutral test by a mutimeter shows continuity?
If the test shows that there is a continuity between the phase leg and the neutral with no load connected, then that circuit should not be energized. If the circuit was energized then the fuse or breaker protecting that leg will trip the circuit open.
What happens if neutral of three phase four wire system is break?
For a balanced three-phase load, the neutral current is zero, so the loss of the neutral would have no effect.However, for an unbalanced load, the 'difference' between the line currents results in a neutral current.So, for an unbalanced load, if no neutral current can flow, then the load's neutral point will no longer remain symmetrical, and the line voltages will become unbalanced. If the unbalance is severe, then individual loads may be subject to over-voltages or under-voltages.
What happens if phase wire touch to earthing?
When a phase line touches the neutral by any conducting material means the Short Circuit. If there is a short circuit then the current in that circuit will be much higher and this increase in current may damage the the devices that are connected to that line.
How does a phase leg connect to a neutral in an electrical circuit?
A phase leg connects to the neutral through the connected load.
In a 240 volt single phase circuit A phase is 4000 watts B phase is 7000 watts what is the neutral load?
Question is incorrect. in a 240 Volt single phase circuit, how can you have A phase and B phase?
Can you use 3 phase circuit as 3 separate single phase circuit?
yes we can use as a single phase circuit because at practise directly the 3-phase circuit is made by combining the three single phase circuits
What will happen if a phase and neutral test by a mutimeter shows continuity?
If the test shows that there is a continuity between the phase leg and the neutral with no load connected, then that circuit should not be energized. If the circuit was energized then the fuse or breaker protecting that leg will trip the circuit open.
Why would you put a fuse on the neutral side of an electrical circuit?
It does not matter what line in (the phase or neutral) is the fuse. In a closed series circuit current in all areas of the circuit is equal. It's best to put the fuses in both wires (phase and neutral) and even better for each individual device in the chain.
What happens when phase to phase line is connected?
If there is a voltage differential from phase to phase, and a conductance (inverse of resistance) between them, then current (amperes) flows. This is no different than phase to neutral, i.e. voltage across conductance generates current, (I = EC, or I = E/A) except that neutral current is zero in a true phase to phase connection.Note that phase angle is always relative. In phase to neutral, it is relative to (typically) neutral; while in phase to phase, it is relative to the other phase. By Fourier Analysis, the difference between two phases of the same frequency, but of different phase angles, is still a sine (or cosine) wave. Also, by Kirchoff's Current Law, (implied, and I will (sort of) not repeat it here), current entering from one phase and equally leaving via another phase will not reflect at all in the neutral conductor.The simple answer is that connecting phase to phase is a short circuit, just like connecting phase to neutral.CommentThere is no such thing as 'phase to phase' or 'phase to neutral'. The correct terms are 'line to line' and 'line to neutral'.
What happens when any phase conected to ground?
You get a short circuit.
Why fuse will get burnt when phase and neutral get connected?
A fuse is an overcurrent protection device, which protects a circuit by melting in the event of either a sustained overload current, or a short-circuit current. A short-circuit current will occur when a line (not 'phase') conductor makes direct contact with a neutral (or earth) conductor.
What happens if neutral of three phase four wire system is break?
For a balanced three-phase load, the neutral current is zero, so the loss of the neutral would have no effect.However, for an unbalanced load, the 'difference' between the line currents results in a neutral current.So, for an unbalanced load, if no neutral current can flow, then the load's neutral point will no longer remain symmetrical, and the line voltages will become unbalanced. If the unbalance is severe, then individual loads may be subject to over-voltages or under-voltages.
What happens to temperature during a phase change?
Temperature is constant during a phase change.
What happens if phase wire touch to earthing?
When a phase line touches the neutral by any conducting material means the Short Circuit. If there is a short circuit then the current in that circuit will be much higher and this increase in current may damage the the devices that are connected to that line.
What is the need for neutral wires in circuits for electrical services?
The neutral provides a path back to the source for the electricity. In a three-phase circuit, it is mainly used to carry the unbalanced load back to the source. In theory, a perfectly-balanced three-phase circuit would not need a neutral, but this is almost impossible to achieve in actual practice.
