The Modbus RTU protocol is available through the RS-485 port. The RS-485 port can be used as a Modbus RTU server device. The supported Modbus function codes are 3 (Read Holding Registers) and 4 (Write Holding Registers). The default Modbus ID is 240. The ID can be changed through the service port using Vaisala Insight software and a USB adapter.
The following table lists the default communication settings used when Modbus is enabled at the factory (chosen when ordering).
Description | Default value |
---|---|
Baud rate | 19200 |
Parity | No parity |
Number of data bits | 8 |
Number of stop bits | 2 |