Hall effect sensor is a reliable sensor working on the principle of Hall Effect. It can be used to sense position or R

1. HALL EFFECT AND SENSORS

2. Switches and Sensors
 There are many methods to detect the
positions of the surfaces such as landing
gear positions or landing gear doors.
 The are the possible sensors/ switches.
◦ Mechanical switch actuated by linkages or the
door itself.
◦ Reed switch.
◦ Proximity switch
◦ Hall effect sensor.

3. Mechanical Versus Electronic
 The mechanical switches have moving
parts, which will wear off. It is effected by
environmental and vibration.
 The proximity and hall effect sensors have
to moving parts and can be hermetically
sealed.
◦ These sensors can last much longer.
◦ It is easier to test the system.

4. Hall Effect Principle
A thin sheet of semiconducting material (Hall element) through which a current
is passed. The output connections are perpendicular to the direction of current.
When no magnetic field is present, current distribution is uniform and no
potential difference is seen across the output.

5. Hall Effect with magnetic field
When a perpendicular magnetic field is present, a Lorentz force is exerted on
the current. This force disturbs the current distribution, resulting in a
potential difference (voltage) across the output. This voltage is the Hall
voltage (VH). The interaction of the magnetic field and the current is shown
in equation.

6. A Simple Sensor
 Take note of the
elements..
◦ Hall elements
◦ Amplifier
◦ Transistor
switch
The sensor will detect the target and a small voltage is induced by the Hall
element. The voltage is amplified and switch the transister on.

7. Hall Effect Sensor used for RPM
sensor

8. RESOURCES
My Blog CAA UK Recommended Books
Title Author
Aircraft Electricity and Eisman 0-02-801859-1
Electronics
Art of Electronics Horowitz 0-521-37095-7
Horowitz /Hill /Hill
Elements of Electronics Hickey/ 0070286957
Villines
Learning Modern Aviation Helfrich 0-13-118803-8
Electronics
electronics-
tutorials.ws/electromagnetism/ Micro Electronics in E Pallet 0-273-08612-X
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