The J21K differential pressure switch monitors the difference between two system pressures or vacuums and senses excessive flow deviation, or verifies that a filter is clogged.


The J21K's rugged design - with epoxy coated enclosure and sealed metal bellows - lends itself to exacting applications.  Widely used in refrigeration (chiller) and compressor applications, the J21K can be used for filter status monitoring and proof of flow.





21K Series Overview

Differential Pressure Switch




  Rugged, NEMA 4X, epoxy coated enclosure

  SPDT switch output

  Welded 316 stainless steel or brass sensors

  Unique isolated sensor design

  Adjustable ranges:

       • 30 "Hg Vac to 90 psid

       • 1 bar Vac to 6,2 bar d

  UL listed and cUL certified

  Optional ATEX or GOST intrinsic safety compliance

  Designed to meet Enclosure Type 4X

  SPDT switch output

  Adjustable deadband option for precise on-off control

  Brass or welded stainless steel bellows sensors

  External manual reset option




Designed to meet Enclosure Type 4X (with

   watertight conduit fitting)

UL listed and cUL certified

Optional ATEX and Rostechnadzor (GOST-R)

   intrinsic safety compliance

Optional adjustable deadband

Single switch output

Opposing bellows design


J21K Series Customer Drawings


10104 - Type J21K, Models 127 & S127B


9704 - Type J21K, Models 140 & 150, S140B & S150B,

          16020 & 16021


9384 -  Type J21K, Models 232


9813 -  Type J21K, Models 254


8833 -  Type J21K, Models 357






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