How to set EcoStruxure BMS Server as Modbus TCP Server or Modbus RTU Server (Slave)

[Product_Support]

Issue

A 3rd party system wants to poll data from EcoStruxure BMS server through Modbus, how to set it up?

Product Line

EcoStruxure Building Operation

Environment

• Building Operation Automation Server
• Building Operation Automation Server Premium
• Building Operation Automation Server Bundled
• Building Operation Enterprise Server

Cause

If an EcoStruxure BMS server needs to share data with a 3rd party system through Modbus, the EcoStruxure BMS server can act in one of two roles: Modbus TCP server or Modbus RTU Server (Slave)

EBO server acting as RTU slaveEBO server acting as Modbus TCP server

Resolution

1.  Create a Modbus interface under the EcoStruxure BMS server and define the Modbus device ID for the EcoStruxure BMS server.
2. Create Modbus points under this Modbus interface and set the register numbers and register type for the points.
3. Create a Modbus Slave network for serial connection, select the COM port and set relative communication parameter. Or create a Modbus TCP Server for TCP connection and can change the default Modbus TCP port if needed (Usually just leave it as default).
4. Use standard Modbus test software like Modscan to scan the points through TCP or serial.
   1. Use Function Code 1 or 2 to read Digital Modbus points and Code 3 or 4 for Analog Modbus points.
   2. Be sure to match the data length setting in Modscan with the real points number in the EBO server. For instance, if there are only 3 values in EBO Modbus interface, the data length setting must be less than 3 in Modscan. Or it will show error in Modscan.

The below video will demonstrate how to configure EcoStruxure BMS server to act as Modbus TCP server or Modbus RTU slave