Reed switches in Blowers

Blowers or centrifugal fans are used in various fields to move air or other gases from one area to another, either to vacuum or exhaust an area, or to to add positive pressure to clean rooms et cetera. When used in such applications to ensure positive pressure inside a room, or to ensure that noxious gases and vapors are exhausted through a water jacket to neutralizing before atmospheric exhaust, it is important that the flow rate of the gas be monitored.
Reed Switches in blowers and vacuum ducts consist of a vane with a tiny light magnet is fitted across the flow of air, inside the duct. The reed switch or sensor is mounted outside the duct. Nominal flow of air lifts the vane and keeps it near the reed sensor. If the rate of blowing or sucking decreases due to dust collection in the filters or saturation of the water jacket in the case of exhausting, the reed switch does not get actuated. This signal is used to trigger a “filter change” LED or to also trigger an alarm in critical applications.
Application Classification
Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or Relay, Temperature Sensing or Magnet Biasing types. This application is classified as follows and the link gives more information on best practices to help select the most suitable AT band and matching magnet.
Position sensing Type
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Position Sensing type application When an application requires the end position of a movement sensed, or the sensing of a part when it
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Nov 7, 2020 |
Recommended Products
The Reed Switches and Sensors used in such applications need to be robust, durable and efficient in meeting a high life expectancy. Our engineers work hard in life testing our products under various conditions, and our intention is to ensure end product durability and life. Although we wouldn’t want to restrict any of our products for use in only certain applications, the recommended products for use in this application are listed below.
MS-324 Miniature Flat Pack Reed Sensor with Actuator
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Drawing of MS-324 Magnet Sensor starFeatures10W Contact Rating. Normally Open contact. Three sensitivity bands. Sputtered Ruthenium
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Oct 30, 2020 |
RM-1318 Reduced Miniature Reed Switch
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The RM-1318 Reduced Miniature reed switches are designed for applications where a size restriction is present, but a higher Contact
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Nov 8, 2022 |
SM-1322 Sub Miniature Reed Switch
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This Form A type SM-1322 Sub Miniature Reed Switch is built with a 2.25 mm diameter glass with a higher wall thickness for better glass to
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Nov 8, 2022 |
MS-214 Miniature Cylindrical Sensor
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Drawing of MS-214 Magnet Sensor starFeatures10W Contact Rating. Normally Open contact. Three sensitivity bands. Sputtered Ruthenium
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Oct 30, 2020 |