Skip to end of metadata
Go to start of metadata

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 5 Next »

Introduction to MODBUS

The CTM-ONE can support 4 types of MODBUS:

  • MODBUS Master Gateway

  • MODBUS Slave Gateway

    • TCP Slave

    • Serial Slave

    • Self-Slave

The mode setting of the serial port must be set to MODBUS for the RS232/RS485 port setting for MODBUS configuration to work even if no physical RS232 or RS485 devices are physically connected to the CTM-ONE.

image-20240415-213800.png

MODBUS configuration is available on the CTM-ONE local web interface under serial < modbus tab.

image-20240415-214310.png

The RS232 and RS485 tabs expand for specific MODBUS functionality. The CTM-ONE supports simultaneous RS232 and RS485 protocols so individual configurations can exist for either protocol.

For Ethernet-based MODBUS communication (TCP / RTU over UDP), either MODBUS RS232 or RS485 can be used.

image-20240417-183024.png

The “Mode” defines the Gateway Master or Gateway Slave operating state.

image-20240417-183136.png

Access must also be enabled for routing data via the wireless network when using MODBUS. This can be found under Configuration > Firewall > Service Access Rules.

image-20240422-160448.png

Make sure that field “Enable this rule” is checked off.

image-20240422-161003.png

  • No labels