VFD Belden Cable Shielding

[Chris Elston]

So I wondered what everyone else thought about this. I know what I do, but what do you do? If you have an Allen Bradley VFD drive, cable tray, and Belden 1000V VFD rated motor cable running 300 feet. Do you: Sheild only ONE end of your cable back to your panel, so the noise generated gets drained back to the panel. Sheild only ONE end of your cable back to your VFD frame, so the noise generated gets drained back to the drive. or Sheild BOTH ends of your cable, to the panel and motor end? Just wondering what you EM guys would say...comments? About how the noise is escaped? Also, has anyone any experienced a VFD drive freaking out an ultra sonic sensor? (24vdc)

[beegee]

basic rules are: shield 1 side of the cable if you want to keep noise out of the cable. The side you have to shield is the board side since you try to get a star connection for signal grounding. If you have the possibilty use a different frame ground from the PE. shield both sides if you want to keep noise in. So for the VFD this is the case. If you are running 300Feet you'd better put a choke or Sinus filter behind your VFD. This will also solve a lot of problems with noise.

[dogleg43]

You should check with the drive manufacturer. We worked on a very large project with many AB 1336 and 1305 VFD's. At that time (1998) AB had very specific cabling guidelines and we were told to ground the shield on BOTH ends. We did this and did not have any problems. But things change and it may be different now.