CERRXIAN RS232 to RS485 Serial Passive Converter DB9 Female Communication Data Transmitter Screw Terminal Connector Adapter

RS232 to RS485 / RS422 converter. It easily lets you connect any RS485 or RS422 device directly to COM port. Features: 1.Interface: Compatible with EIA/TIA RS-232C standard and RS-485 standard. 2.Electronic interface 1: At the side of RS-232 is a DB9 female(hole-type?connector. 3.Electronic interface 2: At the side of RS-485 is a DB9 male(needle-type)connector with connection board. 4.Working mode:Asynchronous,half-duplex,differential transmission. 5.Transmiision media:Twisted pair or shielded twisted pair(STP). 6.Transmission rate:300-115200bps. 7.Mechanical dimension: 95mm x 33mm x 17mm 8.Working environments: 0~70??model H/S/C)?-20~85?(model I).Relative humidity 5% to 95%. 9.Transmission distance:1200m(RS-485),5m(RS-232). Hardware installation and application: This converter use traditional DB9/Female and DB9/Male connectors.Output connection board has four poles.You can use twisted pair(TP) or shielded twisted pair(STP) and easily to assemable or disassemble. "D+/A" is positive signal, "D-/B" is negative signal, "+5V/+12V" is external power input if need, "GND" is public ground wire. Communication needs at least 2 connections (D+/A,D-/B).Connecting the same polarity signals together.If you use STP,the "GND" signal must connect too. This converter supports 2 communication modes as below: 1.)Point to point,2 wires,half-duplex. 2.)Point to multi-points,2 wires,half-duplex. When this converter works at the end of the network,it needs to install a terminal resistance(normally 120?,1/4w),for preventing signal reflection and interference.