digital methane alarm miner's lamp

digital metahne alarm miner's lamp ..Applicable scope Used in underground worke like coal mines and other mine tunnels. 2.Product Features (1).main use:for the safe lighting,the detection of methane concentration and the exceeded concentration warning in coal mines containing explosive gas. (2).alarm mode:sound,light alarm. (3).measurements show the error:no more than the true value low than five percent. (4).error alarm:not more than 0.01% CH4 (5).reality way:three red 0.8 inches LED display. (6).real-time clock display:the apparatus showing real-time “hours” and “minute” in accordance with the 24-hour clock. 3.Main technical parameters: Rated capacity Rated voltage Working current Battery life span Largest lamp illumination Testing scope Lamp time Main light source Detection alarm circuit 4AH 3.7V 150mA 120mA 500times per time Larger than 1400LX 0%-4%CH Larger than 11 hours