... -20mA,Expandable channe Gas monitor, GAS DETECTING SYSTEM ,GAS DETECTOR ,for toxic and combustible gas,Temperature&Pressure signalFeature:1.Standard 4U tray- ... detector is 4~20mA signal.3.Monitoring combustible gas detector, toxic gas detector, flame detector, pressure sensor and temperature ... data memory ,can store fault records,alarm records, on/off records and event records by category ,data is ...