The Benefits and Limitations of Limit Switches

Limit switches are electromechanical devices that detect when an object moves further than its predetermined limit, quickly interfering to prevent it from causing unwanted damage. Most often, they are used alongside industrial machinery as a way to keep individual moving parts working at their best. As a form of proximity sensor, they follow a set of principles which are designed to observe once an object has passed a defined limit to its movement. However, unlike similar sensor devices, limit switches detect movement by making physical contact with the target object. This simple mechanical design offers certain advantages as well as a few major limitations. While there are a plethora of variations, this article will focus on limit switch designs that are used in the control and actuation of industrial valves.

How Do They Work?

Most standard limit switches are electromechanical devices that consist of a mechanical actuator linked to a series of electrical contacts. When an object comes in contact with the actuator, the actuator plunger’s movements cause the electrical contacts within the switch to either close or open their electrical connection. Specifically, they use the mechanical movement of the actuator plunger to control or change the electrical switch’s state. When referring to the limit switches used with industrial valves, they typically contain one or more magnetic or electrical switches that are operated by the rotational or linear movement of the valve. Using their various switches and actuators, the device is able to show whether the valve is open or closed and if the valve actuator is properly positioned or beyond its normal travel limits. Such information can be used to trigger a safety mechanism or inform the operator of potential issues.

Advantages and Limitations of Limit Switches

Limit switches are fairly simple in comparison with other similar devices, and their straightforward design allows for easy installation that can work well in almost any industrial setting. They also feature low power consumption while maintaining high accuracy and the ability to handle high-inductance loads. Moreover, limit switches can be used to switch multiple loads and have heavy-duty electrical contacts that are similarly able to switch higher levels of current than other comparable proximity sensors. That said, because they rely on mechanical action, limit switches are generally limited to equipment that operate at relatively low speeds. As a device with moving parts, they are also subject to mechanical wear and fatigue over time and will need eventual replacement.

Installing Limit Switches

If you plan to apply limit switches to a valve assembly, there are a list of factors to consider during the installation process. First, it is important to determine what indications are necessary for the effective control and monitoring of the valve operation. Limit switches can be made to indicate the status of an assembly at certain times or to react on a moment-by-moment basis. Regardless of your situation, it is helpful to consider what your limit switch will need to indicate and when. Additionally, there are plenty of environmental factors to consider. Be sure to accommodate for the local conditions and hazards where the switch is installed, in addition to ensuring the power rating matches that of the connected component(s).

Conclusion

Switches and sensors are crucial devices for protecting industrial projects that involve moving parts. If you are in the market for electrical and electronics components like limit switches, there is no better source than Integrated NSN. Here on our website, we provide our customers with access to a world of new, used, obsolete, and hard-to-find components that have each been sourced from accredited manufactures on our Approved Vendor List (AVL). When you need top-grade industrial parts fast, we have you covered with expedited shipping options and a user-friendly catalog of available parts. For more information, you may contact us at any time via phone or email; we are available 24/7x365!

1. paul butler
2. Posted on March 23, 2023
aviation part types