1. How Does A Magnetic Speed Sensor Work - Speed
Sensor
_____________________________________________________________________________________
By Austin Bennet - http://speedsensor.org/
For centuries speed sensors have been used to determine the speed of moving objects. In fact, the very
first primitive speed sensors were lengths of rope with a knots tied in them that were tossed over the
sides of moving ships to determine how many "knots" the ship was traveling at. However; the advent of
the motorized wheeled carriage created the need for a more advanced mechanical speed sensor, such
as the type that used a gear and a cable to run a speedometer on an automobile.
To Learn More About Speed Sensor
A Technological Need
As time and technology progressed however, the need for other types of accurate speed sensors
developed. This in turn led to the development of what is often referred to as the magnetic speed
sensor. So how do they work? How can a magnet detect and transmit the speed of a moving object
The Hall Effect
It is not just the magnet in a magnetic speed sensor that is used to determine speed but an electrical
current that surrounds the magnet as well. There is a certain electrical phenomena called the "Hall
effect" that is used to determine the speed of an object with a magnet.
An Electrical Current

2. In short, when an electrical current is ran near a magnet and the magnet detects ferrous metal such as
iron or steel the electrical current is effected. This electrical effect can then be transmitted by wires to a
speed gauge where it can be displayed.
Gear Toothed Magnetic Sensor
Often a gear is used in conjunction with a magnetic speed sensor. As the gear spins or turns, each spline
or tooth in it will be detected by the magnet as it passes and a corresponding electrical pulse is sent out.
The faster the gear spins the faster the electrical pulses the sensor sends and thus a speed reading is
made.
So… What’s Next ?
To learn more about Speed Sensor, Click Here: http://speedsensor.org/