... to RS485 signal or positive. It is no-power needed SW485WA is a converter that change RS232 signal ... to RS485 signal or positive. It is no-power needed, It can supply optic-electrical isolation only ... worked on 3 lines 3. Support 2500V isolation, no power supply needed4. Automatic send data control, auto ... 5% to 95%Power Input poweredNo power supply needed, powered from TXD, RTS, DTR signal in ...