Modbus RS485 / M-Bus Master - Gateway.

The HD67029-xxx are M-Bus / Modbus Slave converters.
They allow to monitor M-Bus meters (like SIEMENS, Kamstrup, Maddalena, Sontex, etc. meters) with a Modbus Master net (like a PLC exc).

On M-Bus side, the HD67029 can manage up to 250 meters.

M-Bus / Modbus - Converter
( Master M-bus: up to 20 slaves - Modbus Slave Port: 485)