In order to produce a high-quality end result, automating industrial processes requires numerous different components to operate flawlessly together. Position sensors, a modest but crucial element in industrial automation, are the subject of this article. Position sensors in manufacturing and processing facilities ensure that crucial tasks are accomplished as planned, which aids in the monitoring and management of production processes.To be more precise, their principal job is to find “targets” or moving things and report on their presence or absence. Pneumatic valves have a variety of uses because they may transmit signals to the system telling it to carry out a preprogrammed action when a target is within a preset distance of the position sensor.

The position sensor delivers a signal telling the system to stop carrying out that pre-programmed function or switch to an other function when the target moves away from the position sensor. Although the target may theoretically be anything, this article will solely examine metallic targets and the “mainstream” methods for locating them for the sake of simplicity. Mechanical limit switches, inductive proximity sensors, spring limit switches, and limit switches are some of these technologies. Understanding the standard language used by the majority of sensor manufacturers is helpful before reviewing the many types of position sensors.

• Sensing range: the separation between the sensing face and the switch-activating target

• Hysteresis: the distance between the release point and the switch’s actuation point

• Repeatability: The switch’s lifetime capacity to consistently identify the same target inside the same range.

• Response time: the interval between target detection and output signal generation.

limit switch that is mechanical

Electromechanical devices called mechanical limit switches use direct physical contact with a target to sense the target’s position. They can support high current loads and operate without a power source. Mechanical switches don’t care about polarity or voltage because they employ dry contacts, making them resistant to various electrical flaws such electrical noise, radio frequency interference, leakage current, and voltage drop. The lever arm, button, body, base, head, contacts, terminals, and other moving elements of these switches frequently require maintenance. Votto mechanical limit switches might have poor repeatability since they are in direct physical touch with the target. The target itself as well as the lever arm may become worn through physical contact. There are also unprotected openings that are susceptible to corrosion, dust, and moisture. Due to this problem, certified hazardous areas and sealed contacts frequently come at a high price.

Limit spring switch

A spring limit switch is an electromechanical tool that uses magnetic attraction to determine the location of a magnetic target. Two little metal prongs enclosed in a glass tube are located inside the switch. A “reed element” is what this is. Due of its magnetic sensitivity, the reed element responds to magnetic targets by activating. Since they don’t require direct contact with the target to function, spring limit switches provide all the benefits of mechanical switches while avoiding wear difficulties.

Normal ferrous targets cannot be utilized with spring limit switches; magnetic targets are necessary. The reed switch is unreliable because the reed element, the glass tube, and the little metal prongs become fatigued by bending. Low contact pressure might result in chattering of the contacts and erroneous signals from the reed in high vibration situations.

Sensors for Inductive Proximity

A solid-state electronic device called an inductive proximity sensor uses changes in the energy field of a metallic object to determine where it is. Physical touch is not required, and there are no moving parts to jam, wear out, or damage, which lowers maintenance. It is also resistant to dust and filth because it has no moving parts. Inductive proximity sensors are very adaptable for a range of applications and are available in a number of sizes and designs. Inductive proximity sensors cannot tolerate high current loads and need an external power source (electricity) to function. They might also be vulnerable to voltage drops, leakage currents, radio frequency interference, and electrical noise. Extreme temperature swings and moisture penetration can occasionally be bad for inductive proximity sensors.

limit limit switch

Utilizing a special hybrid technology, limit limit switches can locate ferrous targets via electromagnetic fields. Leverless limit switches are incredibly dependable in challenging situations and long-term use. Since there is no need for physical touch or external power, huge current loads are feasible and nothing can jam, bend, shatter, or grind. Similar to mechanical switches, they are impervious to electrical noise, radio frequency interference, leakage currents, and voltage drops. They are also neither polarity- or voltage-sensitive. Dust, grime, dampness, physical touch, and the majority of corrosives or chemicals have no effect on limit limit switches. The majority of types have a wide working temperature range and are intrinsically safe. The leverless limit switch is perfect for applications that require watertightness and explosion proofing due to its sealed connections and solid metal enclosure.

Position sensors are crucial to the automation of industrial processes. There are numerous position sensor technologies on the market, each with a distinct set of performance traits. In order to attain the necessary performance and reliability, care should be made to choose the right type of sensor for the application.