Delta AX-3 Series, Operation Manual

Page: 318 / 370

AX - 3 S e r ie s O p e r a t i o n M a n u a l
9 - 8
_9
9.2 Introduction to Modbus Serial Communication
9.2.1 Modbus Serial Port
DIADesigner-AX supports the following Modbus network types, including one RS-232 and one RS-485. Each Modbus
Serial Port allows one master. A maximum of 32 slaves can be attached to a master. But since RS-232 has no multipoint
capability, only point-to-point connection is possible. And only the FIRST slave can communicate with the master. Since
RS-485 has multipoint capability, RS-485 does NOT have such limitations. Follow the below section to set up the basic
settings for communication via the serival port for the Modbus serial port.
9.2.1.1 Adding Delta Modbus COM
1. Right-click the PLC in the tree view to open up a conext menu. And click Add Device… to open the Add
Device setting window.
2. Find Delta Modbus COM (Fieldbuses -> Modbus -> Modbus Serial Port -> Delta Modbus COM) and then
double-click it or click Add Device to add this port in.