To enable IC485IP powered by interface ( port powered ), make connections as below.

PC RS232 CTS to IC485IP RS232 RTS
PC RS232 RTS to IC485IP RS232 CTS
PC RS232 DTR to IC485IP RS232 DSR
PC RS232 DSR to IC485IP RS232 DTR

Basically if any three of above connections are connected, there will be enough power to operate IC485IP.  If all above four connections are connected, there will have maximum power for IC485IP.

Power supply is needed to operate IC485IP if IC485IP is connected to an embedded system instead of a PC. This is because embedded system RS232 connector usually have only TX, RX, and GND, therefore IC485IP is not able to take power from CTS, RTS, DTR, and DSR.

IC485IP does not include power supply which is optional for order.