Rockwell Automation System Design for the Control of Electrical Noise - Manual (Page 24)

Publication GMC-RM001A-EN-P — July 2001
2-6 High Frequency (HF) Bonding
Noise Solutions Using the
Ground Plane Principle In this section, examples of how to apply the ground plane principle
are described.
Grounding to the Component Mounting Panel
In the example below, the drive chassis ground plane is extended to
the mounting panel. The panel is made of zinc plated steel to ensure a
proper bond between chassis and panel.
Figure 2.5
Drive chassis ground plane extended to the panel
Note: Where TE and PE terminals are provided, ground each
separately to the nearest point on the panel using flat braid.
Plated vs. Painted Panels
In an industrial control cabinet, the equivalent to the copper ground
layer of a PCB is the mounting panel. To make use of the panel as a
ground plane it must be made of zinc plated mild steel or if painted,
the paint must be removed at each mounting point of every piece of
metal-clad equipment (including DIN rails).
Zinc plated steel is strongly recommended due to its inherent ability
to bond with the drive chassis and resist corrosion. The disadvantage
with painted panels, apart from the cost in labor time to remove the
Drive ground plane (chassis)
bonded to panel