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how does the current flow in a three phase circuit when neutral is not connected?

A balanced three-phase 4-wire circuit - one with equal currents in all three live wires - has zero current flowing in the 4th wire, the neutral. Therefore the neutral wire can be removed, leaving just the three live wires.

Instantaneously, the sum of the three currents is always zero in a balanced three-phase circuit. As an example, when the current reaches its peak in one wire, say 10 amps, the current in the other two wires is one half, 5 amps, in the opposite direction. Therefore the two wires take the return current for the first wire. This state of affairs happens continuously at every instant in the AC cycle, so three lives wires are all that is needed.

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Why neutral not conect in 3phase motor?

A 3 phase motor does not require a neutral conductor because the impedances that make up the stator coils are of equal magnitude and it is what is known as a balanced 3 phase load. If the loads of a wye connected 3 phase system were unbalanced, i.e. the load currents in each of the 3 phases are different, then the unbalanced currents would require a return path to the service transformer via a neutral conductor. The neutral conductor is the transformer centre tap and is usually earthed locally. ANOTHER ANSWER The impedance of each phase winding of a three phase motor is identical (we call it a 'balanced load'). For a star (wye) connected motor, the phasor sum of three identical phase currents is zero, so no current will flow through a neutral, so a neutral isn't required. For a delta-connected motor, there is no provision for a neutral.


What are the advantages of three phase induction motors over the other motors?

A Single phase induction motor includes a main winding, an auxiliary winding, a run capacitor, & a subsidiary star device. The auxiliary winding is configured such that the number of turns of the aauxiliary winding through which a current flows, varies according to the operating mode of motor. When the motor starts, the number of turns of the auxiliary winding through which a current flows is reduced there by increasing the start efficiency of the motor. when the motor runs in normal mode, the number of turns of auxiliary winding through which a current flows is increasing there by increasing the operations efficiency of motor


What is an ac motor?

An AC motor is an electric motor that runs on alternating current, like household electricity, as opposed to a DC motor that runs on direct current from a battery. Most AC motors work from the mains supply, which has a frequency of 50Hz in the UK and 60Hz in the USA. Other types are available that work like stepper motors and need a specialist supply to run them.


How star delta helping motor from overheat?

star delta motors start as a Y for 3 phase so the windings that normally see 480 volts see 277V a relay switches to delta then it runs as a normal delta motor the reduces the starting current by about 60% for 3 phase


How do you connect bulb in 3 phase power?

by using star connectionAnswerIt depends on the type of three-phase supply. If it's a three-wire system, then you can connect the lamp between any pair of line conductors. If it's a four-wire system, then you can connect the lamp either between any pair of line conductors or between any one line conductor and the neutral conductor. Of course, the voltage rating of the lamp must match the line-to-line voltage or the line-to-neutral voltage.

Related Questions

Why neutral not conect in 3phase motor?

A 3 phase motor does not require a neutral conductor because the impedances that make up the stator coils are of equal magnitude and it is what is known as a balanced 3 phase load. If the loads of a wye connected 3 phase system were unbalanced, i.e. the load currents in each of the 3 phases are different, then the unbalanced currents would require a return path to the service transformer via a neutral conductor. The neutral conductor is the transformer centre tap and is usually earthed locally. ANOTHER ANSWER The impedance of each phase winding of a three phase motor is identical (we call it a 'balanced load'). For a star (wye) connected motor, the phasor sum of three identical phase currents is zero, so no current will flow through a neutral, so a neutral isn't required. For a delta-connected motor, there is no provision for a neutral.


Why you use three phase electricity?

Three phase is used mostly with electric motors! Greater power with less current and more economical also. Motor runs cooler and starts quickly with improved starting torque.


How can you make a car that runs 6 feet without electricity?

Just put it in neutral on a hill. But what good is a car that only runs 6 feet?


What are the advantages of three phase induction motors over the other motors?

A Single phase induction motor includes a main winding, an auxiliary winding, a run capacitor, & a subsidiary star device. The auxiliary winding is configured such that the number of turns of the aauxiliary winding through which a current flows, varies according to the operating mode of motor. When the motor starts, the number of turns of the auxiliary winding through which a current flows is reduced there by increasing the start efficiency of the motor. when the motor runs in normal mode, the number of turns of auxiliary winding through which a current flows is increasing there by increasing the operations efficiency of motor


Why single phase induction motor always runs below the synchronous speed?

For exactly the same reason as three-phase motors always run below synchronous speed. If they were to run at synchronous speed then no voltage and, therefore, no rotor current will be induced into the rotor to drive it.


Do Phase 10 runs have to be the same color?

No, Phase 10 runs do not have to be the same color.


Do runs in Phase 10 have to be the same color?

No, runs in Phase 10 do not have to be the same color.


Do the runs in Phase 10 have to be the same color?

No, the runs in Phase 10 do not have to be the same color.


What runs but cannot?

Motors, watches, refrigerator


What is an ac motor?

An AC motor is an electric motor that runs on alternating current, like household electricity, as opposed to a DC motor that runs on direct current from a battery. Most AC motors work from the mains supply, which has a frequency of 50Hz in the UK and 60Hz in the USA. Other types are available that work like stepper motors and need a specialist supply to run them.


What runs but cannot walk?

Motors, watches, refrigerator


How star delta helping motor from overheat?

star delta motors start as a Y for 3 phase so the windings that normally see 480 volts see 277V a relay switches to delta then it runs as a normal delta motor the reduces the starting current by about 60% for 3 phase