... functionButton4 ButtonsAlarmIntermittent multi-level alarmDetection range setting (Adjustable)0~50000ppm(default)0~10000ppm(programmable)2. Main functions:2.1 The real ... independent address 485 communications interface, communication rate 9600,14400,19200 (default),28800,38400 bps (programmable set), 15KV ESD protection, 8 separate ...