The main function of the TD321D485H / TD521D485H series is to convert a logic level signal into isolatedRS485 diferential level signals. The special integrated IC technology of the RS485 transceiver achievesisolation between the power supply and the signal lines isolation, doesRS485 communication andprotects the bus all in one and the same module. The product's isolated power supply withstands a testvoltaae of up to 3000VDC, Also, they can easily be embedded in the user's end eauipment to achievefully functional RS485 network connections.