Posted 8 Mar 2019 On one of our installations we have a noise issue with a long segment of profibus. Will installing snap-on ferrite cores help, hurt or make no difference. I've heard both. One side says proper grounding is more important and that the beads will round off the leading and trailing edges. The other side says the beads are always helpful in noisy environments. Share this post Link to post Share on other sites
Posted 9 Mar 2019 Profibus over rs-??? or ethernet? Share this post Link to post Share on other sites
Posted 10 Mar 2019 (edited) Try this article by a SMAR engineer http://www.smar.com/en/technical-article/tips-for-trouble-shooting-on-the-profibus-dp Other technical articles not specific to Profibus on that site, too Or this one: https://procentec.com/about/news/2016/a-short-guide-to-addressing-emc-on-profibus/ Edited 10 Mar 2019 by DanW additional link Share this post Link to post Share on other sites
Posted 12 Mar 2019 In my prior job the ferrite cores were used on one segment of the profibus where it connected to a DC sputtering power supply to prevent noise. It was standard with the OEM manufacturer to use these where the sputtering supply is located. I have found noise in profibus was caused by two things. One is the connectors, if the cable is damaged and the ground is not secure to the connector it would cause problems. Usually caused by improper installation. The wires have to be stripped perfectly to be installed in the connectors. I had a profibus cable stripper that removed the correct length of insulation to be installed in the DB9 connectors. I have also found noise problems in the cable in several machines where the cable was getting soaked by oil from the rotary vane vacuum pump and had discolored the cable. Since you said it is a long run of cable, I would inspect it for damage or if the cable is getting wet by any liquid. Mike 1 person likes this Share this post Link to post Share on other sites