Rockwell Automation 1397 DC Drive Firmware 2.xx - Manual (Page 242)

CE Conformity B–10
Publication 1397-5.0 — June, 2001
System ground must be extended to all connected enclosures and
components by running a ground conductor with the power and
signal conductors to these enclosures and components, as shown in
Figure B.7. Follow the electrical cabinet guidelines described in this
Appendix for all remote electrical enclosures.
Figure B.7
Ground System and Conduit Screen Termination
Main Electrical
Cabinet Electrical Components
such as Remote Operator
Stations and Motor
Terminate the Screen to
ground at both ends
Terminate ground wire to
ground at both ends
Shielded Cable or Conductive Conduit
The minimum cross–sectional area of a copper ground conductor
shall be per EN60204-1: Safety of Machinery - Electrical equipment
of machines - Part 1: General requirements, section 5.2, Table 1.
The ground conductor must be secured at both ends in a solid
connection. Poor termination of a ground connection is the single
biggest source of EMC problems. For connections, use fittings
intended for solid, long–term connections to a grounded surface, or
continue the screen or conduit beyond the cabinet barrier to a ground
terminal or copper bar extension. Fittings should be rust resistant. It
is preferred to terminate the screen or conductive conduit to a system
ground copper bar internal on the back of the panel and not rely on
the conduit fitting to maintain the ground circuit. Shielded cable
should use a drain wire for the electrical bonding of the shield to the
ground system.
Wiring guidelines are provided here for wiring that is external and
internal to the electrical cabinet and also for specific components.
External Wiring Guidelines – External control, signal, and power
wiring must be in shielded cable or rigid continuous conductive
conduit.
If the system includes a remote operator station that is connected to
the 1397 Drive, the operator station wiring must be in rigid
continuous conductive conduit. Shielded cable cannot be used for
the operator station.
NOTE: Many flexible metal conduit products have not been
designed for RF containment and are not adequate to maintain
compliance.
Wiring the Equipment