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The S637 Sail Switches respond to the air velocity in heating or warm air ducts, such as used in farm crop dryers. The switch completes a 24V or line voltage burner control circuit only when the blower or fan has produced a predetermined air velocity.

  • Micro Switch SPDT snap switch is operated by metal sail inserted in an air stream.
  • Has a set of normally closed contacts which can be used to energize a signal or warning circuit when the velocity drops off.
  • Sail can trimmed to one-half the original size to double the velocity required to close the snap switch contacts.
  • Switch differential can be manually adjusted by turning a knurled knob on the snap switch.
  • A conduit knockout is located on each end of the case for wiring convenience.
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Manuals (1)
Max Temp (F):




Insertion Length:


Contact Ratings:

8.0 A @ 120 Vac

5.1 A @ 240 Vac

2.0 A @ 24 Vac

15.0 A @ 6 Vdc

7.5 A @ 12 Vdc


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