This is a very easy to use low cost semiconductor Gas sensor Module with analog and digital output. This module uses MQ4 Methane gas sensor as a gas sensing element. It requires no external components just plug in Vcc & ground pins and you are ready to go
Sensitive material of MQ-7 gas sensor is SnO2, which with lower conductivity in clean air. It make detection by method of cycle high and low temperature, and detect CO when low temperature (heated by 1.5V).
PCF8591 Module Analog to Digital Converter Module is a breakout board/Prototype Board for PCF8591 IC. The PCF8591 is a single-chip, single‑supply low‑power 8‑bit CMOS data acquisition device with four analog inputs, one analog output, and a serial I²C‑bus interface.
This is a simple RS232 to RS485 converter that is self powered using the TX, RX or RTS, CTS signals for power. The RS232 is DB9 female connector, and the RS422 side is a DB9 male or 4 position terminal block.
The DO output interface can be directly connected to a micro-controller IO port, if there is a block detection sensor, such as the speed of the motor encoder can detect.
DO modules can be connected to the relay, limit switch, and other functions, it can also with the active buzzer module, compose alarm.
