The HD67671 is a BACnet Slave / Modbus Master Converter and it allows you to connect a BACnet Master (for example a Supervisory System…) with some Modbus slaves.

The HD67672 is a BACnet Slave / Modbus Slave Converter and it allows you to connect a BACnet Master (for example a Supervisory System…) with a Modbus Master (for example a PLC, HMI…) in order to exchange the information between the networks.

The HD67712 is a BACnet Master / Modbus Slave Converter and it allows you to connect some BACnet slaves with a Modbus Master (for example a PLC, HMI).

HD67671-IP, HD67672-IP, HD67712-IP supports both BACnet/IP and BACnet/Ethernet.

The connection to BACnet is done over Ethernet.
The connection to Modbus is done over RS232 or RS485.

HD67671-MSTP, HD67672-MSTP, HD67712-MSTP supports BACnet MSTP.
The connection to BACnet is done over RS485.
The connection to Modbus is done over RS232 or RS485.