MQ-8 Hydrogen Gas detection and Door Release system
with Arduino, Node MCU, ESP32
A gas detector is a device that detects the presence of gases in an area, often as part of a safety system. This type of equipment is used to detect a gas leak or other emissions and can interface with a control system so a process can be automatically shut down. This type of device is important because there are many gases that can be harmful to organic life, such as humans or animals. Gas detectors can be used to detect combustible, flammable, and toxic gases and oxygen depletion. My inspiration to build this device is to give an alert of a gas leak before it affects human life. Due to gas leaks and blasts, many of them lost their life.
MQ-8 Hydrogen gas mostly released from battery units while getting charged is not healthy to inhale rather it is dangerous. Hence in cases where battery systems are located it is advisable to install Hydrogen gas detection system, provide visual indication as well as sound alarm system. As a pre-caution the door lock should be released so that if any person is inside the battery charging room he could quickly move out.
MQ-8 Hydrogen Gas Sensor Interfacing with Arduino:
This sensor has 4 pins of which VCC and GND of the sensor are connected to 5volt DC and ground of Arduino board. Digital OUT of the Sensor is connected to any Digital Pin 7 of Arduino which will trigger Pin 9 connected to relay to open the door. Analog OUT of the Sensor may be connected to any Analog Pin of Arduino A0 to A5 then but we shall connect to Pin A0.
There are two LEDs and one buzzer connected of which Green LED will light when Arduino is switched on to indicate Power on. This is connected to Pin 2 of Arduino. Red LED and buzzer will switch on Digital out Pin 7 goes High. Red LED and buzzer are connected to Pin 3 and Pin 4 of Arduino.
MQ-8 Hydrogen Gas Sensor Interfacing with Node MCU:
This sensor has 4 pins of which VCC and GND of the sensor are connected to 3.3volt DC and ground of Node MCU board. Digital OUT of the Sensor is connected to any Digital Pin GPIO7 of Node MCU which will trigger Pin GPIO9 connected to relay to open the door. Analog OUT of the Sensor may be connected to any Analog Pin of Node MCU ADC0.
There are two LEDs and one buzzer connected of which Green LED will light when Arduino is switched on to indicate Power on. This is connected to Pin GPIO2 of Node MCU. Red LED and buzzer will switch on Digital out Pin 7 goes High. Red LED and buzzer are connected to Pin GPIO3 and Pin GPIO4 of Node MCU.
MQ-8 Hydrogen Gas Sensor Interfacing with ESP32:
This sensor has 4 pins of which VCC and GND of the sensor are connected to 3.3volt DC and ground of ESP32 board. Digital OUT of the Sensor is connected to any Digital Pin GPIO7 of ESP32 which will trigger Pin GPIO9 connected to relay to open the door. Analog OUT of the Sensor may be connected to any Analog Pin of Arduino ADC0.
There are two LEDs and one buzzer connected of which Green LED will light when Arduino is switched on to indicate Power on. This is connected to Pin GPIO2 of Arduino. Red LED and buzzer will switch on Digital out Pin GPIO7 goes High. Red LED and buzzer are connected to Pin GPIO3 and Pin GPIO4 of ESP32.
In all the three cases like Arduino, Node MCU and ESP32 the relay is energized by microcontroller and the door lock which was held due electromagnetic force drops out and it is as good as the lock is open and people can just move out.