Unbalance in the Rotor of the Motor

It is not difficult to isolate the cause, but the problem cannot always be quickly rectified Cause 2 can easily be discovered. If present and set right Cause 4 leads to instant vibration and load humming, and of course to generation of heat and smoke from the shorted turns; Coil repair or rewinding is inevitable. Cause 3 shows up if the vibration intensity waxes and wanes as the motor speeds up from rest and passes through the various natural frequencies of vibration of the supporting structure, if the foundation is of solid masonry, his cause may not be present. Cause 1 will be discovered, if present, during trial runs before and after coupling. This leaves causes 5 and 6 which need not be further isolated as both can be rectified by rebalancing the motor with its shaft fitment at site. Dynamic balancing is necessarily done at two distinct planes. Complete balancing can only be done with the rotor dismantled.