German Keller sensors Keller models Keller prices

Keller sensor is a sensor that measures the air flow drawn into the engine. In electronically controlled gasoline injection engines, to obtain the optimal mixture concentration under various operating conditions, it is necessary to accurately measure the amount of air drawn into the engine at every instant, using this as the main basis for the ECU to calculate (control) the fuel injection quantity. If the air flow sensor or wiring fails, the ECU will not receive the correct intake air signal, preventing normal control of fuel injection quantity, which will cause the mixture to be too rich or too lean, resulting in abnormal engine operation.

Keller sensor classification

1) Potentiometric displacement sensors convert mechanical displacement into resistance or voltage output with a linear or arbitrary functional relationship. Ordinary linear potentiometers and circular potentiometers can be used as linear displacement and angular displacement sensors, respectively. However, potentiometers designed for displacement measurement require a definite relationship between displacement change and resistance change. The movable brush of the potentiometric displacement sensor is connected to the measured object. The displacement of the object causes a resistance change at the moving end of the potentiometer. The magnitude of the resistance change reflects the magnitude of the displacement, while an increase or decrease in resistance indicates the direction of displacement. Typically, a supply voltage is applied to the potentiometer to convert the resistance change into a voltage output. In wire-wound potentiometers, the resistance changes in steps based on the turn resistance as the brush moves, resulting in a stepped output characteristic. If such a displacement sensor is used as a displacement feedback element in a servo system, excessive step voltage can cause system oscillation. Therefore, the resistance per turn should be minimized during potentiometer manufacturing. Another major disadvantage of potentiometric sensors is susceptibility to wear. Their advantages include simple structure, large output signal, ease of use, and low cost. 2) Magnetostrictive displacement sensors precisely detect the absolute position of a moving magnetic ring using non-contact measurement technology to determine the actual displacement value of the measured product; the high precision and high reliability of these sensors have been widely applied in thousands of practical cases. Since the moving magnetic ring that determines the position and the sensitive element do not come into direct contact, the sensor can be used in extremely harsh industrial environments and is not easily affected by oil stains, solutions, dust, or other contaminants, with an IP protection rating of IP67 or higher. In addition, the sensor uses advanced materials and electronic processing technology, allowing it to operate in high-temperature, high-pressure, and high-vibration environments. The sensor output signal is an absolute displacement value; even if power is interrupted and reconnected, data is not lost, and re-zeroing is not required. Since the sensitive element is non-contact, repeated detection does not cause any wear to the sensor, significantly improving detection reliability and service life. Magnetostrictive displacement sensors utilize the magnetostrictive principle, generating a strain pulse signal through the intersection of two different magnetic fields to accurately measure position. The measuring element is a waveguide, with the sensitive element inside the waveguide made of special magnetostrictive material. The measurement process involves generating a current pulse in the sensor's electronics chamber, which travels through the waveguide, creating a circumferential magnetic field outside the waveguide. When this magnetic field intersects with the magnetic field generated by the moving magnetic ring sleeved on the waveguide (which changes with position), a strain mechanical wave pulse signal is generated within the waveguide due to the magnetostrictive effect. This strain mechanical wave pulse signal travels at a fixed speed of sound and is quickly detected by the electronics chamber. Since the transmission time of this strain mechanical wave pulse signal within the waveguide is proportional to the distance between the moving magnetic ring and the electronics chamber, measuring the time allows for highly precise determination of this distance. Because the output signal is a true absolute value, rather than a proportional or amplified signal, there is no signal drift or value change, and periodic recalibration is not required. Magnetostrictive displacement sensors are high-precision, long-stroke absolute position measurement displacement sensors manufactured based on the magnetostrictive principle. They employ a non-contact measurement method; since the moving magnetic ring used for measurement does not directly contact the sensor itself, friction and wear are avoided, resulting in long service life, strong environmental adaptability, high reliability, good safety, and ease of system automation. Even in harsh industrial environments, they can operate normally. Furthermore, they can withstand high temperatures, high pressures, and strong vibrations, and are now widely used in the measurement and control of mechanical displacement.

Keller sensor working principle

Magnetostrictive displacement (level) sensors utilize the magnetostrictive principle, generating a strain pulse signal through the intersection of two different magnetic fields to accurately measure position. The measuring element is a waveguide, with the sensitive element inside the waveguide made of special magnetostrictive material. The measurement process involves generating a current pulse in the sensor's electronics chamber, which travels through the waveguide, creating a circumferential magnetic field outside the waveguide. When this magnetic field intersects with the magnetic field generated by the moving magnetic ring sleeved on the waveguide (which changes with position), a strain mechanical wave pulse signal is generated within the waveguide due to the magnetostrictive effect. This strain mechanical wave pulse signal travels at a fixed speed of sound and is quickly detected by the electronics chamber. Since the transmission time of this strain mechanical wave pulse signal within the waveguide is proportional to the distance between the moving magnetic ring and the electronics chamber, measuring the time allows for highly precise determination of this distance. Because the output signal is a true absolute value, rather than a proportional or amplified signal, there is no signal drift or value change, and periodic recalibration is not required.

Keller sensor application areas

Widely applicable for level measurement and control of various liquid tanks in industries such as petroleum, chemical, water conservancy, pharmaceuticals, food, and beverages, as well as aerospace refueling systems, automotive refueling systems, diesel refueling systems, various hydraulic tanks, hydrological monitoring, and water treatment. Magnetostrictive displacement sensors are high-precision, long-stroke absolute position measurement displacement sensors manufactured based on the magnetostrictive principle. They employ an internal non-contact measurement method; since the moving magnetic ring used for measurement does not directly contact the sensor itself, friction and wear are avoided, resulting in long service life, strong environmental adaptability, high reliability, good safety, and ease of system automation. Even in harsh industrial environments (such as those prone to oil stains, dust, or other contamination), they can operate normally [01]. In addition, they can withstand high temperatures, high pressures, and strong vibrations, and are now widely used in the measurement and control of mechanical displacement. Their stroke can reach 3 meters or longer, with a nominal accuracy of 0.05% F·S, and for strokes over 1 meters, sensor accuracy can reach 0.02% F, S, with repeatability up to 0.002% F·S, making them widely used in petrochemical, aerospace, electric power, water conservancy, and other industries.

Weidou Intelligent Technology specializes in selling German Keller sensors, Keller proximity sensors, Keller distance sensors, Keller vision sensors, Keller displacement sensors, Keller torque sensors, Keller speed sensors, Keller photoelectric sensors, Keller position sensors, Keller angle sensors, Keller tactile sensors, Keller temperature sensors, Keller pressure sensors, Keller flow sensors, Keller level sensors, Keller motion sensors, Keller process sensors, original German imports. Welcome inquiries and orders from users.