What types of non-contact sensors are available
Non-contact sensors can record the position, speed, temperature, air quality, and distance without contact. These sensors are solid-state electronic devices that generate an electromagnetic field or beam to detect any interference in that particular field. These sensors require less maintenance because the fixed parts are used for scanning. The following are some common sensor types used in non-contact sensor designs. The technology used in a particular sensor largely depends largely on the parameters or conditions monitored (e. g. temperature, pressure, vibration, position, etc.).
A non-contact liquid level sensor refers to a liquid level sensor that can measure the liquid level without touching the liquid. Non-contact liquid level sensors have been made with different technologies, such as ultrasonic, radar, optical, capacitance, etc. Non-contact measurement method has the advantages of no moving parts, no liquid contact, fluid with no pollution, smaller volume, longer life, lower cost for some applications, suitable for acid and corrosive fluids (some models), no cutting, no opening (some models), etc.
A contactless laser displacement sensor is a noncontact sensor technology that uses a triangulation of the reflected beam to determine the movement or position of the target within the measurement range. The semiconductor laser generates a beam that is sent to the target through an emission lens. The light reflected from the target passes through the receiving lens in the sensor and focuses onto the detector element, such as the CCD (charge-coupled device) array. As the target changes its position relative to the sensor, the angle of the reflected light will change, resulting in the light focusing on different parts of the detector element. Changes in the light position can be analyzed and used to determine the position of the target.
A contactless temperature sensor (also known as a thermoometer) can check its temperature without using any device. It is mainly used to test the surface temperature, and its reaction time is faster and more accurate than the thermocouples. Target will wear using thermocouple measurements during moving, rolling or scouring but not non-contact temperature sensors. The contact test device takes time to warm up, but the contactless temperature sensor gives a reading in a relatively short time.
What are the characteristics of the non-contact sensors
Non-contact sensors often rely on techniques based on electrical, magnetic, optical, acoustic waves, or other principles, rather than physical contact or mechanical motion to obtain readings. Non-contact sensors are suitable for continuous fast measurements. Sensors typically emit a form of energy, such as radiation, which can be used to detect conditions without physical contact. The object being sensed or detected is often called the target.
Long service life is also one of the characteristics of non-contact sensors. Noncontact rotation sensor is based on the magnetic noncontact sensor principle. Therefore, they are wear-free and extremely tolerant to external effects, but they show an impressive long life, precision, and resolution.
Non-contact sensors are often able to withstand worse conditions than contact sensors. They are more resistant to dust and dirt. And even in harsh working conditions, contactless sensors can provide very accurate data.
