Dear,

Rock is getting on loaded in Y01 conveyor. Y11 conveyor gets the feed from Y01. Y11 is running with two motors in master slave mode and load sharing mode. Motors are being driven by AB VFD. PLC is being used for intercommunication between VFDs. Set point for master motor is given from C/R. System runs normal during normal load period. When sudden heavy load comes on conveyor then slave motor gets over-speed and system trips.

Regards

 

I believe you mentioned both master and slave motors are connected to the same conveyor.

If that's the case, when the master is overloaded, the slave tries to make up by increasing torque.

If both the master and slave is loaded simultaneously (as it should be) there's no way that the slave motor alone can over speed.

If the slave over speeds it means it is not receiving any load and the torque increased (as programmed) is getting converted into speed.

It like the analogy of a train having two engines. However power each engine produces, both can achieve only the same speed.

Please verify.

 

Is there the possibility that despite the use of VFDs, the motors are locking up at full voltage?

Regards,
Phil Corso