The Importance of a Hall Effect Speed Sensor

Posted by maryparker on August 31st, 2012

Have you ever heard about Hall Effect Speed Sensors? They are transducers that work with the help of magnetic field, and their working is based on the principle called Hall Effect. The usage of these devices is increasing day by day. After the invention of these sensors, the electronic field has witnessed a lot of developments. Here we are discussing about the important facts of these sensors.

We all know that the Hall Effect was discovered in 1869 by Edwin Hall. According to Hall Effect, when a current is passed through a conductor, which is placed perpendicular to the magnetic field, a voltage known as Hall Voltage is generated. The semiconductor material used in Hall Effect is known as a hall element. If we do not apply a magnetic field to the hall element that carries the current, then the hall voltage will be zero.

You might have heard about the Lorentz force that acts on a point charge. This is the force experienced by the charges when the magnetic field exists is not parallel to the direction of motion of moving charges. Lorentz force is the basic principle behind the Hall Effect. Hall Effect Speed Sensors work based on the above principles, and it is important to note that we need both electric and magnetic effect for this. A Hall Effect Speed Sensor is well-known for its high-speed operation.

Some of the applications of a Hall Effect Speed Sensor are current sensing, power sensing, proximity detection and speed detection. This device is most widely used in computers especially in keyboards when high reliability is required. It is also used in printers to detecting the missing paper as well as opening covers. A Hall Effect Speed Sensor is a solid state device that consists of several components. These components include: a p-type semiconductor material (hall element), a dc power supply, a magnet and a voltage source.

In a Hall Effect Speed Sensor, the semiconductor material must be placed perpendicular to the magnetic field. The semiconductor materials which usually use are gallium arsenide, indium antimonide, or indium arsenide. If we place a Hall Effect Speed Sensor in a magnetic field, the flux lines would apply a force on the semiconductor material. Thus, the charge carries like electrons and holes would be deflected to either sides, and as a result a potential difference would generate. This is how the device works basically.

The Advantage of Hall Effect Speed Sensors

Hall Effect Speed Sensors can guarantee unlimited number of operating cycles because of its non contact operation results in no friction at all. Another advantage of this device it the high speed operation it provides. Unlike capacitive sensors, a Hall Effect Speed Sensor will not be affected with the air, dust and water. This device has a wide temperature range and it can also be used to measure zero speed. It also provides a highly repeatable operation, and moreover, it is able to measure large current. In short, these devices are durable, efficient and reliable.    

If you want to get more details about other types of sensors like Hall Effect Current Sensor, you can have a look at the following site where you can find all about Hall Effect Sensors.