Rockwell Automation 8720MC High Performance Drives Installation Manual - Manual (Page 26)

Publication 8720MC-IN001D-EN-P — December 2002
1-14 Installing Your 8720MC Drive
Bonding Multiple Subpanels
Bonding multiple subpanels creates a common low impedance exit
path for the high frequency energy inside the cabinet. Subpanels that
are not bonded together may not share a common low impedance
path. This difference in impedance may affect networks and other
devices that span multiple panels. Refer to the figure below for
recommended bonding practices.
Figure 1.5
Multiple Subpanels and Cabinet
Planning Your Panel Layout This section outlines the practices which minimize the possibility of
noise-related failures as they apply specifically to 8720MC
installations. For more information on the concept of electrical noise
reduction, refer to System Design for Control of Electrical Noise
(publication GMC-RM001x-EN-P).
Establishing Noise Zones
When a regenerative power supply (8720MC-RPSxxx) is used in the
8720MC system and mounted right of the drive, observe the following
guidelines when laying out your panel (refer to figures 1.6, 1.7, and
1.8 for zone locations).
Recommended:
Bond the top and bottom of each subpanel to the cabinet using
25.4 mm (1.0 in.) by 6.35 mm (0.25 in.) wire braid.
Scrape the paint around each fastener to
maximize metal to metal contact.
Bonded cabinet
ground bus to
subpanel