Controller problem! (Urgent)

Hi all,

My working area is Stacker Cum Reclaimer{SCR (L&T)}. I am facing a strange problem. we are using two ABB 800 vvvf drives here. one for Slew (for doing left-right BOOM conveyor) and other is for LT(for Long Travel SCR). we are communicating all drives and Encoder by profibus cable.

Now problem is that when we travel SCR, an error is comes in profibus cable adapter and Incoming ACB get tripped. Sometime primary controller is switches on to secondary controller. Strange thing is that sometime problem occurs 20-30 times in one hour and sometime it dont come for 24-36 hours.

what we did till now is that we disconnected ACB trip command and give permanent 110V to respective relay(auxiliary contactor). but after that our control supply getting tripped so we provide seprate control supply. After that boom conveyor motor is tripping. We disconnect motor encoders as they only use in auto mode which not used here and changed the whole profibus cable. At every step we got relief for 24-36 hours.

Any suggestions or ideas are welcomed….