will a 3phase motor continue to rotate if one of the lines b

will a 3-phase motor continue to rotate if one of the lines becomes open? Will the motor be able to start on such a line?

Solution

If motor is operating at higher load (near to the rated load), motor speed will drop gradually to zero. depending upon amount of the load and inertia of the load connected. For high inertia loads, it may take even more time to reduce the speed to zero positively rotating fields continues to rotate the motor and develop the torque demanded by the load. The negatively rotating field, the field associated with the lost phase, produces currents in inductive loads resulting in voltages in the faulted leg of the three-phase supply. These voltages may be nearly equal to the phase voltage that was lost.