Point level switches are used to detect when a liquid has reached a predefined level.
They are designed to detect the presence or absence of a fluid at a specific point. This type of technology is ideal for liquid measurements where monitoring intermediate levels is not important. Point level switches are typically used to control low or high liquid levels in a tank or vessel to prevent equipment damage, over spill, loss of valuable fluids or service interruption.
Float switches in both horizontal and vertical configurations, ultrasonic sensors, and optical sensors can all perform the role of point level monitoring for a range of liquids. Integrating these with additional output connections will communicate point measurements to control or alarm systems.
So… Why should you choose an Optical Point Level Switch over Conventional Level Switches?
Drawbacks of Conventional Point Level Switches
Both vertical and horizontal float switch for point level monitoring, can suffer from reliability issues and short lifetime. A typical float point level switch requires substantial contact with fluid before a signal is registered and action is taken. This may be sufficient in a limited number of applications, but various industries typically require a more accurate and robust level measurement solution.
Ultrasonic point level switches are can also suffer from inaccuracies if used in complex device designs or to measure fluids that can interfere with the sensor’s returning echo signal. Foam or bubbles within liquid can limit the accuracy of ultrasonic point level monitoring and are an expensive option for a relatively simple application.
The primary component of an optical level sensor is a hard-wearing polymer or glass tip that houses an infrared (IR) light source and an optical detector. When the tip is in air, the IR light reflects off the inside of the sensor tip and is reflected into the optical detector. Conversely, when submerged in liquid, this IR light refracts out of the tip and the optical signal is reduced.
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SST Sensing offers a wide selection of optical sensors that can reliably function as point level switches to help prevent flooding or run-dry conditions. The Optomax range of optical sensors are our broadest range, which offer small and compact designs that are able to detect the smallest amounts of fluid in a tank or vessel. These solid-state devices offer long service in applications as varied as flood prevention and industrial monitoring. They are also unaffected by adverse process conditions or ambient light, offering the most precise point level monitoring possible.
Point Level Switches from SST Sensing
SST Sensing is one of the world leaders in optical level sensing technology. We supply an extensive range of optical sensors suitable as point level switches, with success in sectors as varied as food and beverage processing, off high way vehicle fuel monitoring, leak detection in telecoms and automation equipment.
If you would like more information about using one of our advanced optical level sensors as a point level switch in your applications, please do not hesitate to contact us directly.