RS-485 interface converters convert from RS-485 to RS-232. They are used either as pure protocol converters from Modbus TCP to Modbus RTU, or they work as RS-485 bus masters and thus enable communication with several RS-232 end devices per assigned RS-485 address. A typical scenario is the communication of a host PC with several RS-232 laboratory balances or the addressing of several RS-232 frequency converters via a host PLC.