Does an EMC/EMI filter, like https://www.valinonline.com/products/508-110, go before the VFD or after the VFD on the cable that goes to the spindle? Also, if I use a filter on the output side of the VFD, would this protect both the VFD and the motor?

 

regardless of manufacturer EMC/EMI are used in the input side of VFD. Mainly to decrease high frequency interference from both supply side & VFD side to interact with normal operation.

 

The filter on the output side of the VFD doesn't protect both, no VFD and no motor - it decrease EMC/EMI level produced by VFD itself simply.