The MQ-9B is a CO and CH4 gas detection sensor form Winsen. The sensing material of the MQ-9B is SnO2, which has a low conductivity in clean air. It detects carbon monoxide（1.5V）by method of cycling high and low temperature. The sensor's conductivity gets higher with the CO and CH4 gas concentration rising. The sensing range is 10-500ppm CH4. A simple circuit makes measuring this change in conductivity and turning it into data fairly straight-forward, but does require some calibration.
For easy Solderability; use our Gas Sensor Breakout Board.
