freon gas detection sensor MQ139 MQ 139 MQ-139 R134A halogen module

mohon order packing kardus https://www.tokopedia.com/arduinouno/tambahan-packing-kardus-bubble #. size : 32mm X22mm X30mm L * W * H #. the main chip : LM393, NH3 gas sensing probe #. the working voltage : DC 5V Four characteristics: 1, with the signal output LED indicates ; 2 , dual signal output ( analog output , and TTL level output ) ; 3, TTL output valid signal is low ; ( lights lit when the output is low, which can be accessed microcontroller IO port ) 4 , analog output increases with the concentration , the higher the concentration the higher the voltage ; 5 of ammonia with high sensitivity and selectivity ; 6, with a long life and reliable stability ; 7 , rapid response and recovery characteristics ; 8 , with mounting holes for easy fixed installation ; 9 , the probe can plug design for easy testing . V. Application : For household hazardous gas detection device environment , suitable for detection of ammonia vapor , ammonia gas sensors tested concentration range : 10 to 300ppm