Rockwell Automation 1440-TB-C XM-942 Master Relay Terminal Base User Manual
Page 10
10 XM-942 Master Relay Terminal Base
Publication
GMSI10-IN022A-EN-P - May 2010
The grounding wire can be connected to the DIN rail using a DIN Rail
Grounding Block (see illustration below).
DIN Rail Grounding Block
24V Common Grounding
24V to the XM module must be grounded. When two or more power
supplies power the XM system, ground the 24 V Commons at a single point,
such as the ground bus bar.
IMPORTANT
If it is not possible or practical to ground the -24Vdc supply, then it is
possible for the system to be installed and operate ungrounded. However, if
installed ungrounded then the system must not be connected to a ground
through any other circuit unless that circuit is isolated externally.
Connecting a floating system to a non-isolated ground could result in
damage to the XM module(s) and/or any connected device. Also, operating
the system without a ground may result in the system not performing to the
published specifications regards measurement accuracy and
communications speed, distance or reliability.
IMPORTANT
The 24V Common and Signal Common terminals are internally connected.
They are isolated from the Chassis terminals unless they are connected to
ground as described in this manual. See Wiring on page 15 for terminal
assignments.