book collections email follower instructable user

How to Build Your Own Anemometer Using Reed Switches, Hall Effect Sensor and Some Scraps on Nodemcu. - Part 1 - Hardware

FeaturedContest Winner


Since I started with the studies of Arduino and the Maker Culture I have liked to build useful devices using junk and scrap pieces such as bottle caps, pieces of PVC, drink cans, etc. I love to give a second life to any piece or any material. A large part of the materials used here are scrap removed from some equipment and recycled

When I started a project of a weather station for my own I realized that the measurement of the intensity and direction of the wind would not be very easy or cheap. After several months I present to you this project that uses mostly recycled materials and very cheap electronic parts easily found in any electronic store.

This post has 2 parts.

Part 1 - Construction of the devices Anemometer and Wind Vane Direction.

Part 2 - The sketch using Arduino IDE for Esp8266 Nodemcu and transmission to ThingSpeak .

See the video to know the final solution.

How to build your own Anemometer using Hall Effect Sensor and Reed Switches

Project description

The anemometer is a device capable of measuring the wind speed and its direction. Using a Hall Effect sensor we will be able to count how many rotations the cups give in a period of time. The intensity of the wind is proportional to the speed of rotation of the axis. With some simple physics equations, you can determine the linear velocity of the wind, at that moment. We will explain all of them in part 2.

And the direction of the wind we will measure through a windshield with a neodymium magnet and reed switches. The vane points in the direction of the wind and the magnet attached to it will connect the reed switches allowing the electric current to pass through the connection (or connections). Circuits that have positive current indicate the direction of the wind, like a compass.

We have 8 circuits that will emulate 16 directions : 4 cardinal and 4 collateral points when 1 switch is activated (N, NE, E, SE, S, SW, W, NW) and when 2 switches are activated simultaneously we have 8 sub collateral points (NNE, ENE, ESE, SSE, SSW, WSW, WNW, NNW).

The wind speed and direction will be calculated and determined by a sketch in the nodemcu. But this will be explained in part 2. Now let's go to the hardware assembly.

Disclaimer: This anemometer should not be used for professional purposes. It is only for academic or home use.

Note: English is not my natural language. If you find grammatical errors that prevent you from understanding the project, please let me know to correct them. Thank you so much.

Step 1: Bill of Materials

  • Wind Vane

8 x Reed Switches

8 x 10 k ohms resistors

10 cm PVC pipe

2 PVC caps 5 cm diameter

1 PVC cap 2.5 cm diameter

1 CD4051 Analog Multiplexer

1 plastic disk

20 x 20 strong plastic piece

1 Neodymium magnet (The dimensions of the magnet must allow two switches to be connected simultaneously. Mine is 0.5 x 0.5 cm and it is doing well.)

10 different colors wires

1 Generic PCB

1 ball bearing with the same diameter of the aluminum tubes

1 aluminum tube approx 20 cm

1 aluminum tube approx 10 cm

1 hose clamp

Epoxy Mass

Instant Glue - cyanoacrylate and sodium bicarbonate

  • Anemometer

2 Ping pong balls

4 wooden or aluminum sticks approx 12 cm

1 ball bearing

1 aluminum tube approx 5 cm

3 pieces of wires different colors

1 hall sensor SS49E

1 neodymium magnet

Epoxy Mass and Instant Glue - cyanoacrylate and sodium bicarbonate

2 plastic taps approx 3 a 5 cm diameter

1 PVC cap and 5 cm PVC pipe

1 PVC cap 2.5 cm diameter

  • Nodemcu
  • Plastic Case for Electronic Projects
  • Soldering Iron
  • 1 PVC Pipe approx 2 meters and "T" PVC Connector
  • 1 PVC 90 degrees connexion
  • 5V power supply (I'm using solar panel)
Congratulações pelo projeto! Tive ideias muito parecidas com a sua construção, mas faltou-me tempo para realizá-la. O que você fez mostra que fazer do modo simples é sempre o melhor modo. Parabéns pelo trabalho. Saludos, desde Brasil. 73! Waldemar
JustinN13 months ago
n5edd4 months ago
Looks like a good project. I wonder if using hall sensors instead of reed switches would be worthwhile? I realize you have to add a/d functions but then you might not care about higher resolution of wind dir. Just a thought. Well done in any case.
Mtpinto (author)  n5edd4 months ago
Thanks for the feedback. At first I thought to use Hall Effects Sensors to determine the direction but I wanted to try it simpler. About the a / d functions I do not know what I should do to improve the direction measurement. If you can tell me what I should do, I'll gladly try. Best regards.
n5edd Mtpinto4 months ago
No need for a/d function, just a thought. Because you wanted to keep it simple, the way you did it is quite functional. I would just use 2 magnets on the anemometer to keep it balanced but you could use a counter weight too. Still, good job. Cheers...
OscarM1814 months ago
If I could speak your Language like you speak English, I would be a really HAPPY MAN!!! Congratulations and thank you for your project! I am in the middle of constructing it.
Mtpinto (author)  OscarM1814 months ago
Thank you. And thanks to the Google Translator!
If you have any questions during the construction of your project, do not hesitate to contact me. And tell me how it came out. Greetings
pemazzei4 months ago
Belo trabalho! Parabéns!
Mtpinto (author)  pemazzei4 months ago
Obrigado pelo comentario. Grande abraço
JohnC4304 months ago
Since I did not make this I am not sure this tip is feasible.
Power for it could be from a roof mounted small solar panel with a battery backup.
Signal connections via either Blue tooth or transmitter and receiver.
Instead of spending time making this wonderful interesting toy, you could have painted the eaves, facia and Soffits
Mtpinto (author)  JohnC4304 months ago
Thanks for the feedback. You're right with RF or Bluetooth would be good. I am using 6V and 1A solar panel and backup battery. It has worked very well. Regards
NiggyB4 months ago
This is a first-class Instructable. Thank you.
seamster4 months ago
Well done, and nicely presented with loads of info. Thank you for sharing your first instructable! : )
Mtpinto (author)  seamster4 months ago
Thanks for comments, part 2 is already published.
Mtpinto (author)  seamster4 months ago
Thank you very much for the comment. I hope you find it useful. Regards
Mtpinto (author)  Mtpinto4 months ago
Recently I published the second part that completes the project. If you want, take a look. regards
mjrovai4 months ago
Great work! Well written and nicely explained. Congratulations!
Mtpinto (author)  mjrovai4 months ago
Many thanks my friend. Thank you for your support in the development of my projects.The next project we will do together.