Rockwell Automation 22D PowerFlex 40P User Manual, FRN 3 User Manual
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RS485 (DSI) Protocol
Only pins 4 and 5 on the RJ45 plug should be wired. The other pins on
the PowerFlex 40P RJ45 socket must not be connected because they
contain power, etc. for other Rockwell Automation peripheral devices.
Wiring terminations on the master controller will vary depending on the
master controller used and “TxRxD+” and “TxRxD-” are shown for
illustration purposes only. Refer to the master controller’s user manual
for network terminations. Note that there is no standard for the “+” and
“-” wires, and consequently Modbus device manufacturers interpret
them differently. If you have problems with initially establishing
communications, try swapping the two network wires at the master
controller.
Standard RS485 wiring practices apply.
•
Termination resistors need to be applied at each end of the network
cable.
•
RS485 repeaters may need to be used for long cable runs, or if
greater than 32 nodes are needed on the network.
•
Network wiring should be separated from power wires by at least 0.3
meters (1 foot).
•
Network wiring should only cross power wires at a right angle.
I/O Terminal 19 (DSI Shield) on the PowerFlex 40P must also be
connected to PE ground (there are two PE terminals on the drive). See
for more information.
Network Common is internally tied to I/O Terminal 04 (Digital
Common). Tying I/O Terminal 04 to PE ground may improve noise
immunity in some applications.