Isolated Serial Converter Model 485OI9TB is a basic, isolated converter. It converts unbalanced, full duplex RS-232 signals to balanced full-duplex (4-wire) RS-422/485 or halfduplex (2-wire) RS-485 signals. The converter provides 1,500 Volts RMS optical isolation of the data lines and ground (and connected devices) between the RS-232 and RS-422/485 signals. RS-232 port has a female DB9 connector. RS-422/485 port has a 6-position terminal block. The RS-232 side of the converter draws power from the handshake lines (DTR, RTS). At least one handshake line must be asserted (raised high) to power the RS-232 side.The RS-422/485 side must be powered by an external 12 VDC power supply (sold separately).