Rockwell Automation 25B PowerFlex 520-Series Adjustable Frequency AC Drive User Manual - Manual (Page 191)

Rockwell Automation Publication 520-UM001G-EN-E - September 2014 191
RS485 (DSI) Protocol Appendix C
Supported Modbus Function
Codes The peripheral interface (DSI) used on PowerFlex 520-series drives supports
some of the Modbus function codes.
Writing (06) Logic Command
Data The PowerFlex 520-series drive can be controlled through the network by
sending Function Code 06 writes to register address 2000H (Logic Command).
P046 [Start Source 1] must be set to 3 “Serial/DSI” in order to accept the
commands. PowerFlex 523 drives support only Velocity bit definitions.
PowerFlex 525 drives can use Parameter
C122 [Cmd Stat Select] to select either
Velocity or Position bit definitions.
Supported Modbus Function Codes
Modbus Function Code (Decimal) Command
03 Read Holding Registers
06 Preset (Write) Single Register
16 (10 Hexadecimal) Preset (Write) Multiple Registers
IMPORTANT Modbus devices can be 0-based (registers are numbered starting at 0) or 1-
based (registers are numbered starting at 1). Depending on the Modbus
Master used, the register addresses listed on the following pages may need to
be offset by +1. For example, Logic Command may be register address 8192 for
some master devices (e.g. ProSoft 3150-MCM SLC Modbus scanner) and 8193
for others (e.g. PanelViews).
TIP Powerup/Reset the drive after selecting an option for C122 [Cmd Stat Select]
for the change to take effect.