Why neutral not conect in 3phase motor?

Answer 1

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.

Answer 2

This is because the impedances that make up the stator coils are of equal impedance and it is what is known as a balanced 3 phase load. If the 3 loads of a wye connected 3 phase system were unbalanced, i.e. the load currents in each phase are different, then the unbalanced currents would require a return path to the service transformer via a neutral conductor.

Answer 3

The answer that three phase motors are more efficient than single phase motors and require less power to perform the work load required.

To put it in simple terms, the poles in a single phase motor are 180 degrees apart to match the sign wave of single phase current. The poles in a three phase motor are only 120 degrees apart. Therefore, the motor only needs to turn 120 degrees before it receives its next pulse of electricity whereas the single phase motor must turn 180 degrees which requires more initial energy.

Answer 4

3 phase motors don't have a neutral. Your power line in will have a ground and 3 hot wires, L1, L2 and L3. The motor will have 9 wires, T1, T2, T3 etc... The 3 phase motor can be wired up for high voltage or low voltage depending on power supply coming in. Wire up motor for proper configuration ( usually a little wiring diagram on motor / jbox) and check that motor runs in proper direction. If not switch any 2 of the 3 line wires coming in and direction will change.

Answer 5

A neutral wire is used to carry the returning current from electrical equipment back to the source of supply. In a 3 phase system the sine waves on each phase are shifted 120 degrees. So for a balanced 3 phase load, such as a motor, the current to the motor is carried by two phases and the returning current by the other phase.

Answer 6

neutral is only used for single phase motor's.Where we used three phase's in a motor this motor can't use neutral. Three phase motor's inside connected to the rotor and stater.

Answer

If the motor's windings are delta connected, then there is no neutral conductor. If the windings are connected in star (wye) then, because the windings represent a balanced load, there is no neutral current (the sum of the phase currents is zero for a balanced load) -so a neutral conductor would serve no purpose.

Answer 7

As the phase windings of a three-phase motor are identical, it is considered to be a 'balanced' load. The phasor sum (i.e. the neutral current) of the phase currents in a star or wye connected load is zero, so there is no need for a neutral.

Answer 8

A three phase motor uses phase to phase voltage in its operation.