Rockwell Automation System Design for the Control of Electrical Noise - Manual (Page 25)

Publication GMC-RM001A-EN-P — July 2001
High Frequency (HF) Bonding 2-7
paint, is the difficulty in making quality control checks to verify if
paint has been properly removed, and any future corrosion of the
unprotected mild steel will compromise noise performance.
Plain stainless steel panels are also acceptable but are inferior to zinc
plated mild steel due to their higher ohms-per-square resistance.
Though not always available, a plated cabinet frame is also highly
desirable since it makes HF bonding between panel and cabinet
sections more reliable.
Painted Components
Mating surfaces must be cleaned of paint and the exposed surfaces
protected against corrosion with conductive paint or petroleum jelly.
Anodized Aluminum Components
Mating surfaces must be cleaned of anodizing and the exposed
surfaces protected against corrosion.
EMC Filters
Filter performance depends entirely on close coupling between the
filter case and the drive chassis (or other load chassis). They should
be mounted as close as possible to the load and on the same panel. If
a painted panel is used, short braid straps should be used to tie the
two chassis together. As a temporary remedy, an effective means of
coupling filter case and drive chassis is to lay a single piece of
aluminum foil beneath the two chassis.
Doors
For doors 2 m (78 in.) in height, bond with two or three (three is
preferred) braided straps (top, bottom, and center).
EMC seals are not normally required for industrial systems.