Hello,
I have a piece of rolling equipment, it consists of one 7.5HP Motor and one 10HP motor. Each motor powers a separate roller, the load on the rollers spikes high for a brief time as we pass parts through it.
Each motor is controlled separately via a VFD, these are rated at 440V and the supply is 380V AC 3-Phase.
The supply to the machine is isolated via a transformer, steps from 208 line to 380V.
The issue is that I get a high voltage alarm on the VFD's which causes them to shut down. I assume it's when the load quickly drops from peak it causes a high voltage spike.
I'm pretty certain I need a snubber on each output of the VFD, what I don't know is what type of snubber I should use since it's a frequency drive.
How do I calculate the values for an RC snubber for this drive, or should I use something solid state.
Help will be greatly appreciated,
Thanks,
Joe