... standard intelligent sensor, on-site maintenance is very convenient unique LCD with backlighting design technology, field observation, the maintenance ... method Concentration unit:ppm,%VOL,%LEL,mg/m3 Acousto-optic alarm means:, vibration Working temperature: - 40 ~ 70 °C Work ... right now display vibration motor and buzzer, indicator. All alarm 1 times says the normal starting, if electricity shortage ...