Magnet Polarity Detector




About: Gardener, poet, anything aha!

So many shape and type of magnets, like neodymium magnets, ring magnets and anything. But sometimes we need to identify the polarity, and its not easy to identify it. So, in this instructables, i will show you some great idea, how to make Magnet Polarity Detector. And the best thing of this project is you can make a switch using this tools.

OK Let's Make It!


Step 1: You Need

  1. Breadboard
  2. 2 Pcs LED (I use red and blue LED)
  3. 1 Pcs Resistor (i use 4.7 k)
  4. Jumper wires
  5. Old PC Fan
  6. Power supply (i use USB)

Step 2: Open the Fan

Open your old PC fan and take this sensor module. After take the module, solder it for make the foot longer like image 2 (Sorry for my bad Soldering :D)

Step 3: The Circuit

1. Take all of the materials and make it like the circuit image.

  • Green line (jumper wire)
  • Black line (To power supply)
  • Red line (Resistor)
  • Grey line (LED)

2. Insert the sensor module to the breadboard,

3. Insert the resistor

4. Insert the jumper wires like image.

Step 4: Almost Finish

Next, you just follow the circuit image or look the example in the image above. But, if you like soldering, you can use PCB for make it smaller and make it look nice. BTW, after you finish the circuits like image 6, Your magnet polarity detector is ready to use!!!

Time to test it

Step 5: Finish, Let's Test It!


I hope you like this Instructables

thanks for look my works

please like, share ,subscribe, vote this.

Thank you...



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    3 Discussions


    5 months ago

    I made this using your build as a guide. Thanks! I only did two things different. I used an RGB LED and I used pull-down resistors on the Hall Effect Sensor's outputs. My LED glowed a faint Red all the time before I added them. I did some research and I learned that the outputs on the sensor float high so I connected 1K resistors from each output to the positive side of my power supply. Thanks again!


    2 years ago

    great project! To do the job of a compass. fun build though.

    1 reply

    Reply 2 years ago

    thanks for look my works. Have fun :D