Open fridge detection solution

Hi, I am pretty new to electrical components. I have an arduino project where I am trying to make a piezzo buzzer beep when the fridge has been left opened for a minute.

So I am looking for a component that can detect if the fridge door is closed or not.

First I tried a magnetic switch, but noticed that it detected the proximity of the other magnet half from too far away. I am looking for a detector that detects if it is either touching the other half of the switch or 1-2mm away from the other half of the switch.

Looking for suggestions what component I could use or an idea what I should be looking for. Thank you very much in advance to you!

…adjust position of said sensor/switch? Different magnet?

One way or another, some kind of calibration or adjustment will be necessary in order to define the difference between “open” and “closed.”

A limit switch of some sort would likely be the most direct route; those with a lever-style actuator would likely be a bit more forgiving in terms of placement.

HI sutipong,

Alternatively you could measure the temperature inside the fridge and alarm if it is too high, or use light sensor to detect if the fridge’s light is on.

heke, AsamaLab

The two magnet method is not usually appropriate for door/window open alarms.

Try the much more common single magnet operating mode.

If your chosen magnetic switch is not compatible with the common single magnet method, try a more basic magnetically activated device. The classic easiest to use part is a magnetic reed switch.

Here’s an option that should work right out of the box.