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Three phase alternating current systems are either 3-wire systems or 4-wire systems. In the case of a three-wire system, each 'wire' is properly called a line conductor. A four-wire system comprises three line conductors and a neutral conductor.
Line conductors can be identified by letters, or by colours. If they are identified by letters, they can be L1, L2, and L3, or A, B, and C, or R, S, and T -depending on the national/international standard adopted. If they are identified by colours, then these may be red, yellow, and blue, or brown, black, and grey -again, according the the national/international standard adopted.
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Can a 380volt's 3 phase motor can be converted to 230volt's three phase motor?
Only if you want to damage it. "277" Volt 3-phase will usually mean 277 from each phase to neutral, and 480 from phase to phase. By "230 3-phase", you likely mean 120 phase-to-neutral, and 208 phase-to-phase. If you really mean 230, then you are probably NOT talking about a three phase motor.
What does the phases on a nameplate of a motor mean?
On a three phase motor, the phases give you direction for how to hook the motor up to make it spin one direction vs. the other. If you hook up such a motor blindly with all three phases, it may spin in the opposite direction you want; to fix, you swap any two of the three phase connections.
What happens if one leg in a 3 phase synchronous motor fails does it reverse its rotation?
No it does not reverse rotation. If the proper motor protection is used on the motor, the motor should trip off line. Loosing a leg will drive the other two legs of the motor into a higher than normal state. This higher current will be sensed by the overload protection and the motor contactor will drop out. This opening of the motor contactor will drop the supply to the motor and the motor will stop.To reverse a three phase motor, reverse any two feed wires to the motor. This is usually done at the motor's junction box to preserve the wire colour coding of the wires through out the system.AnswerDo you really mean a 'phase' or do you mean a 'line'? This is an example of where the use of correct terminology is important. 'Losing a phase' means losing one of the machine's three field windings, whereas 'losing a line' means losing one of the three supply conductors. Two completely different situations for a delta-connected machine.For example, for delta-connected field windings, the three-phase supply is maintained and the machine assumes an 'open delta' condition, whereas losing a line places two windings in series and in parallel with the third, across a single-phase supply.
What happens if you change phase and neutral in 3 phase circuit?
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' <<>> 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.
What will happened if one phase loss in three phase motor?
The motor will hum and act like it is trying to run it's commonly known as single phasing, it will also heat up quite rapidly and if you set up your circuit correctly and have the proper thermal overload protection on it it will trip and protect the circuit and the motor. If the problem is in the motor winding you will have to rewind the motor or replace it
Reverse motor for phase three?
If you mean to reverse the direction of a three phase motor, you just switch any 2 leads. switch 1 and 2, or 2 and 3, or 3 and 1.
Can a 380volt's 3 phase motor can be converted to 230volt's three phase motor?
Only if you want to damage it. "277" Volt 3-phase will usually mean 277 from each phase to neutral, and 480 from phase to phase. By "230 3-phase", you likely mean 120 phase-to-neutral, and 208 phase-to-phase. If you really mean 230, then you are probably NOT talking about a three phase motor.
What does the phases on a nameplate of a motor mean?
On a three phase motor, the phases give you direction for how to hook the motor up to make it spin one direction vs. the other. If you hook up such a motor blindly with all three phases, it may spin in the opposite direction you want; to fix, you swap any two of the three phase connections.
What will be the effect on an operating 3 phase induction motor if a phase leg is lost?
If the proper motor protection is in place, the motor's contactor will drop out and take the motor off line. If no motor protection is in place the motor will single phase. This will put a higher than normal operating current on the other two legs of the motor's windings.AnswerIf you actually mean 'lose a phase', then you've lost one of the three stator windings (which has become disconnected or burnt out). The machine will behave like an 'open wye' or 'open delta' transformer, and you will still have a rotating magnetic field. If, on the other hand, you mean that you've lost a 'line', then you simply lost one of the three supply conductors and you you will end up with two phase windings in series with each other and in parallel across the third, giving you a single-phase situation with no rotating field but you will have a pulsating field instead. The rotor will continue to run if already running, but will not start.It's important to use the correct terminology with three phase, and not to mix up the terms 'phase' and 'line'.
What is the simplest way to run a 3 phase 380 V motor of about 1 KW directly on 220 V single phase supply without resorting to rewinding or frequency converters?
You cannot run a three phase motor on single phase power. You'll burn the motor up within minutes. By the way, I've never seen or heard of a 380 volt motor. Do you mean a 480 volt motor? If so, the only way you can power it is with the correct full voltage and a 3 phase power supply.
What is mean by pole in three phase motor?
The pole refers to that part of the stator which has windings on it . Two poles are always physically opposite and magnetically opposite.
What does short circit mean?
short circuite means phase to phase,three phase short, phase to earth, three phase to earth, this is all short circuite
What happens if one leg in a 3 phase synchronous motor fails does it reverse its rotation?
No it does not reverse rotation. If the proper motor protection is used on the motor, the motor should trip off line. Loosing a leg will drive the other two legs of the motor into a higher than normal state. This higher current will be sensed by the overload protection and the motor contactor will drop out. This opening of the motor contactor will drop the supply to the motor and the motor will stop.To reverse a three phase motor, reverse any two feed wires to the motor. This is usually done at the motor's junction box to preserve the wire colour coding of the wires through out the system.AnswerDo you really mean a 'phase' or do you mean a 'line'? This is an example of where the use of correct terminology is important. 'Losing a phase' means losing one of the machine's three field windings, whereas 'losing a line' means losing one of the three supply conductors. Two completely different situations for a delta-connected machine.For example, for delta-connected field windings, the three-phase supply is maintained and the machine assumes an 'open delta' condition, whereas losing a line places two windings in series and in parallel with the third, across a single-phase supply.
What does one mean by 3-phase loads?
Electrical circuits are designed in two phase types. Either single phase or three phase. A single phase is one wave of electricity while three phase is three waves that are offset.
Can you break a three phase from a disconnect?
If you mean can you splice in a second circuit from the load side of a three phase disconnect then the answer is no.
What is mean by that a system is a three phase?
There are three "hot" conductors, all at voltage, and 120 degree phase shift apart from one another.
What happens if you change phase and neutral in 3 phase circuit?
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' <<>> 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.
