Hall Effect Sensors: Revolutionizing Position Sensing and Measurement in Industrial Applications
The sensors that fall under the category of Hall effect are essential parts of industrial processes since they can accurately and non-constantly detect and measure magnetic fields. These sensors are also utilized in systems such as speed and current sensing, and also in controlling and detecting the status of motors. With the advancement of industrial automation, there’s an increase in the need for precision and reliability, and thus, the capability to monitor and control the machinery with great accuracy continues to improve the features of Hall effect sensors. For more information on proximity switch sensors and related products, visit OMCH’s proximity switch solutions here: https://www.omchsmps.com/ru/path/proximity-switch/. In this article we are going to explain the technology of Hall effect sensors, their types, applications and why OMCH provides high-quality sensors suitable for the modern demands of the industry.
How Does a Hall Effect Sensor Work?
A Hall effect sensor, in simple words, measures the voltage distinction, called Hall voltage, resulting from interaction of magnetic fields and electric current flowing through a conductor. The working procedure can broadly be divided into the steps listed below:
- Detection of Magnetic Field: A sensor based on Hall Effect consists of a thin slice of semiconductor, which is commonly silicon, with current flowing through it. When a magnetic field is applied orthogonally to the flow of current, it leads to the shifting of charge carriers, electrons or holes, to one end of the material thereby generating a voltage difference across the conductor material.
- Charge measurement: The voltage difference caused by the Hall Effect is directly proportional to the intensity of the magnetic field. The Hall voltage can be measured and applied for measuring or indicating the presence and strength of the magnetic field.
- Output and Signal Processing: The output signal is defined as the strength and direction of the output magnetic field, provided that the parameters of the magnetic field surrounding the sensor are varied. This signal is connected to the control system where it is examined to find the value of position, speed or current of the examined system.
- Changeable: The output, depending upon the configuration of the controller is either analog or digital.
The needle provides an analog output which is a constant signal corresponding to the strength of the magnetic field whereas digital outputs only generate a signal when the needle is moved above a specific threshold field strength.
Due to non-contact sensing techniques, Hall effect sensors can function accurately in hostile conditions, such as high temperature, mechanical shocks, and high humidity, where standard mechanical switches would fail.
Types of Hall Effect Sensors
Each application requires a different type of Hall effect sensor. The Hall effect sensors are mainly divided into the following categories:
Linear Hall Effect Sensors
Linear effect sensors and magnetometers are produced with a range of output values for both the sensor and the magnetic field for which the sensor is utilized. These sensors have a continuous analog output making them useful in applications that require measuring magnetic field strength, current sensing, and position detecting. Such sensors are in great demand for real-time and accurate measurement of magnetic fields in motor control as well as in current monitoring systems, for example in the electric vehicles ‘where they are often used as part of battery management systems in order to safeguard the cells from overcurrent damage. Linear Hall Effect Sensors are one of the most versatile and widely used precision magnetometers available today, used as sensitive electronic compasses for attitude and heading reference systems.
Digital Hall Effect Sensors
Digital Hall sensors provide on/off outputs when a signal in the form of a magnetic field is received. Fields that are above set limits will signal these sensors and allow them to detect the presence or absence of such fields, but the measurement itself is irrelevant. These sensors are suitable, for example, for use in encoders, limit switches in industrial machines and sometimes in cars for proximity sensing. Digital Hall sensors are designed to work with control systems for detecting limits and positions in manufacturing machinery or equipment where the range of movement in one or more axes is limited. These sensors produce an output reaction only when there is a magnetic field aligned to one of its poles. They do not provide an output in the absence of that magnetic field. On the other hand, bipolar Hall effect sensors are responsive to both north and south poles which is very useful for systems where the direction of the magnetic field needs to be detected.
Latching Hall Effect Sensors
Latching Hall effect sensors are latching type sensors which means they are configured to “latch” or maintain their output until removed by a trigger’s magnetic field. With the application of the magnetic field, the sensor’s output changes, and it continues to remain so until the opposite magnetic polarity is applied. Most commonly used Hall sensors include automotive ignition systems sensors and memory devices sensors where the sensor needs a persistent output until an explicit command is given for change.
Applications of Hall Effect Sensors
Because of its precision and dependability, in addition to its non-contact capabilities, Hall effect sensors are used in many industries and for several purposes. Some notable uses are in:
Control and Sensing Rotation Speed of Electric Motors
In systems using brushless DC motors, the position and speed of rotating components are measured through the use of Hall effect sensors. In these motors, the power supply for the motor is better managed by using these sensors. The extensive application of Hall effect sensors in industrial and automotive practices includes their use in tachometers and speedometers for measuring the rotational speed of wheels and shafts.
Electric Current Measurement
Hall effect sensors have gained much popularity as closed-loop current sensors for electrical systems. Through contactless measurement of current in a conductor, Hall effect sensors determine the magnetic field generated by a current. This method of measurement is critical for high voltage systems or dangerous environments where making contact with the conductor becomes unsafe or impossible.
Position Sensing
In the case of hall effect positioning sensors, used in linear actuators and robotic arms, these sensors detect motion or presence of magnetic materials. The sensors serve the purpose of identifying the location of different parts in automated machinery systems for smooth movement recalibration.
Automotive Applications
In the auto industry, Hall effect sensors find use with certain systems such as anti-lock brakes, wheel speed sensors, and electric throttle control. The sensors make it possible to measure rotation of parts, identify position of pedals or wheels, and enable other essential safety systems.
Proximity Sensing
Hall effect sensors function as proximity sensors within a certain range with the presence of magnets or ferrous materials. Those sensors find use in security systems, door mechanized switches, and limit switches where instantaneously accurate position detection is mandatory, and they do not employ mechanical contact. They find their use as proximity sensors in cases like detection of doors being opened or closed and in automation systems requiring stringent positioning.
Why Choose OMCH Hall Effect Sensors?
OMCH’s advanced Hall effect sensors are the perfect blend of quality and reliability, making it easy to meet the demands of various industries. Their high precision, durability, and non-contact functionality makes them ideal for automation, motor control, and position sensing. Regardless of whether you need linear, digital or latching Hall effect sensors, OMCH is ready to provide the most suitable automation solution. Check out OMCH’s proximity switch solutions here.
Conclusion
Hall Effect sensors are crucial for the operations of modern industries as they ensure effective, constant, and non-contact detection of magnetic fields. These sensors are useful for motor control/ speed sensing and current/ position measurement. OMCH offers Hall effect sensors for businesses looking to implement advanced sensing technology to enhance operational efficiency, safety, and reliability.
