... .Features1. Plug and play, small volume, easy installation2. Convert RS-232 data transmit (TXD) and data receive (RXD ... , GNDRS-422 signalD+, D-, GNDWorking formatAsynchronism, point to point or multi point,4 wire full duplexDirectionAutomatic send ... terminal blockEnvironment Working temperature-20 to 60Storage temperature-25 to 85HumidityRelative humidity 5% to 95%PowerInput poweredNo power supply ...