This is an easy-to-use sensor for detecting Carbon Monoxide (CO), ideal for detecting concentrations of CO in the air.The MQ-7 can detect concentrations in the range of 20 to 2000ppm.

The module has an analog output that comes from the voltage divider that forms the sensor and  a load resistor. It also has a digital output that is calibrated with a potentiometer, this output has a led indicator.

Technical  Specification:

• Operating Voltage: 5V DC
• Heating Voltage: 5V (high) and 1.4V (low)
• Load resistance: adjustable
• Heating resistance: 33 Ohm
• Warm Up Time: 60s (high) 90s (low)
• Resistance Consumption: approx. 350mW
• Oxygen Concentration: 21%