[HW] Getting started: Wind speed measurement

Wind speed sensor is really similar to water speed sensor.

It has a paddlewheel with three blades and an hall-effect magnetic sensor.
 
First of all I tried to understand each cable's role:
  • Red: +5v
  • Black: ground
  • Yellow: hall sensor output
Let’s start measurement...
While the sensor is correctly connected to a 5v power source, voltmeter’s jacks are connected to the yellow cable and the black one.
In a complete rotation the value is 2 times 0.5V and 2 times 0.0V.
We can also use an Arduino to measure what comes out from the sensor:
  • Red 5V
  • Black GND
  • Yellow  PIN A0
int sensorPin = A0;    // select the input pin for the potentiometer
int sensorValue = 0;  // variable to store the value coming from the sensor
 
void setup() {
}
 
void loop() {
  // read the value from the sensor:
  sensorValue = analogRead(sensorPin);   
  // print the value:
  Serial.print(sensorValue);                
}
 
Too easy, but it shows exactly what the sensor does!
 
To read with more accuracy the two peaks we need a resistor between 5V pin and the pin we will use as input.
(I used a potentiometer of 22k.)
 
Instead of using a potentiometer or a resistor we could ask Arduino to do that...
"A pin may also be configured as an INPUT with pinMode, and subsequently made HIGH with digitalWrite, this will set the internal 20K pullup resistors, which will steer the input pin to a HIGH reading unless it is pulled LOW by external circuitry."
 
 
 
English
Image: 
Speed sensor
Cables

Comments

Massimo Rossi

Sun, 01/25/2015 - 09:24

Complimenti. Bellisimo lavoro! Che sensore è stato usato? Sembrerebbe uno dei vecchi sensori raymarine.

Vincenzo Emanue...

Mon, 01/26/2015 - 11:30

Raymarine ST50/60

Vincenzo Emanue...

Mon, 01/26/2015 - 14:21

Link al manuale