The HSR-637W universal reed switch has been perfected by HSI engineers to handle high power up to 100 watts, and low power down to 30 mW, all while maintaining low and stable contact resistance. This Form C switch is perfect for circuits that normally run at low levels, but that occasionally experience a surge that would overload a standard switch. With the HSR-637W, you have the versatility to design in one switch to handle both loads seamlessly.

Universal Power Checkboxes


Universal Power Form C Reed Switch


  • Maintains low and stable contact resistance at low level (down to 30mW)
  • Capable of switching both low and high power loads
  • Solid tungsten contacts
  • Switch materials are lead free and RoHS compliant
  • Hermetically sealed contacts
  • Designed for universal power relays or proximity sensors
  • Not ESD sensitive
  • Extended operations in extreme environments



  • Fluid Controls Processing
  • Reed Relays
  • Broadcasting and Video Equipment
  • Security
  • Mobile Phone Base Stations
  • Instrumentation
  • Process Control
  • Automatic Test and Measurement Equipment
  • Industrial

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From 'Making Sense' Blog

HSI Sensing Recognized in the 2019 SIA New Product Showcase at ISC West

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