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RAD-900-...
PHOENIX CONTACT
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PLC/Modbus RTU mode
Figure 5-3
PLC/Modbus RTU mode
Connect the I/O extension modules to the controller directly via the integrated RS-232 and
RS-485 interface by means of wireless communication. In PLC/Modbus RTU mode, the
master wireless module (RAD ID = 01) operates as a Modbus slave. The master wireless
module has its own Modbus address.
Connect I/O extension modules to each wireless module in the network. The I/O data of the
extension module is stored in the internal Modbus memory map of the master wireless
module. In addition, the diagnostic data from all wireless devices is stored here.
Each wireless module must be configured using the PSI-CONF software (from page 74
onwards).
PLC/Modbus RTU dual mode
Figure 5-4
PLC/Modbus RTU dual mode
Dual mode combines the PLC/Modbus RTU mode and the serial data mode. Serial Modbus
devices can be connected to the RS-232 or RS-485 ports, and connect I/O extension
modules to each wireless module in the network.