Fridge Door Alarm project is developed for constructing a fridge door alarm.
This project mainly consists of a IR transmitter, IR sensor, driver section and buzzer.
The IR transmitter is connected at the frame of the fridge and the IR sensor is connected at the door.
When the door is closed, the IR rays transmitted from the transmitter falls on the IR sensor. When the door is opened, the IR rays are deviated and therefore the rays do not fall on the sensor. The signal from the sensor is given to the driver section.
The driver section drives analogue voltage and the analogue voltage is given to a relay. Thus the relay operates a buzzer as long as the door is opened.
Thus when the fridge is opened, the buzzer produces sound and therefore the user will not forget to close the door