# Mesuring the wind force with the tension of an anemometer *HELP*

Hey folks! So, for a class project I have to make a program that mesures the wind force and sends an alert if it goes over 49.709695 mph (80km/h more precisely I'm from france) but I don't have any reference for the anemometer that I got and i'm a bit lost. The only thing I can do is read its tension by pluging it analog. For material I just have the anemometer an arduino uno card. I would be glad if someone helped me with this, i only have 2days left to make the program. Thanks

I don't have any reference for the anemometer that I got

We certainly don't know what anemometer you have.

Shokale: Hey folks! So, for a class project I have to make a program that mesures the wind force and sends an alert if it goes over 49.709695 mph (80km/h more precisely I'm from france) but I don't have any reference for the anemometer that I got and i'm a bit lost. The only thing I can do is read its tension by pluging it analog. For material I just have the anemometer an arduino uno card. I would be glad if someone helped me with this, i only have 2days left to make the program. Thanks

Doesn't matter which anemometer he has as long as it is one that generates a voltage(tension) when it rotates.

You need to look up "voltage divider" and understand what it does. Your anemometer will generate a higher and higher voltage the higher the wind speed. Your Arduino is limited to 5 volts on the analog input pin. exceeding that and you will need a new Arduino board. The voltage divider resistors will limit the voltage getting to the Arduino pin.

To determine the values of resistors needed for the voltage divider, you MUST determine the highest voltage your anemometer can generate. To do this you need a volt meter(DVM) and need to produce a wind of that maximum speed. The easiest to take a ride in an automobile and measure the voltage while holding the anemometer out the window Have the driver drive at the maximum wind speed and see what voltage is produced.

Report back when done.

Paul

On a windless day stick it on the roof of a car and start driving at 80 km/h. See what comes out.