... 1. Fixed type installation 2. Gas detector with lcd display 3. Audible ... features:* 4-20mA, 3 wire connection ,compatible with existing alarm control unit or DCS(Distributed Control ... Multi-parameter backlight LCD display: measuring range,digital gas reading ,units, bar graph , system status etc ... 45 VDC)* Linear output signal: 4~22.8mA with superimposed communication signal for HART protocol * Failure ...