If a phase sequence indicator rotates clockwise for a phase sequence of RYB, then what happens when the phase sequence is changed to BRY?

If a phase sequence indicator rotates clockwise for a phase sequence of RYB, then what happens when the phase sequence is changed to BRY? Correct Answer It will rotate clockwise only.

Concept:

• The direction of rotation of a 3 phase induction motor can be reversed by interchanging any two of the three motor supply lines.
• Let the phase sequence of the three-phase voltage applied to the stator winding is R-Y-B. If this sequence is changed to B-R-Y, it is observed that the direction of rotation of the field is reversed
• Such that the field rotates counterclockwise rather than clockwise. However, the number of poles and the speed at which the magnetic field rotates remain unchanged.
• Thus it is necessary only to change the phase sequence in order to change the direction of rotation of the magnetic field. For a three-phase supply, this can be done by interchanging any two of the three lines.

Application:

A three-phase induction motor connected to a three-phase supply with a phase sequence of R-Y-B rotates in a clockwise direction.

If the phase sequence is changed to R-B-Y, the induction motor will rotate in opposite to its initial direction of rotation i.e. rotate in anticlockwise direction.