United Electric (UE) J21K NEMA 4X General Service Differential Pressure Switches

The UE J21K differential pressure switch maintains the difference between two system pressures or vacuums, senses excessive flow deviation, or verifies that a filter is clogged. It is designed with two separate opposing sensors that are connected by a rod to actuate the snap switch.

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

Key Specifications

  • Adjustable Ranges Within 30" HgVacD to 90 PSID
  • Single SPDT Switch Output
  • UL Listed and CSA Certified
  • Welded 316 Stainless Steel Sensors
  • Repeatability ±1% Adjustable Range
  • Models Available from Stock

Specifications, Manuals, and Supporting Literature

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Model Selection Guide

Use this table to find the right model for your application.  Don't see the option you need? Call a Lesman sales specialist at 800-953-7626

Adjustable
Range
Deadband Proof
Pressure
Working
Pressure Range
Catalog
Number
One SPDT output, brass bellows, 1/4" NPTF process connection
0-6 PSID
0-40 PSID
0.1-0.4
0.3-0.7
6 PSID
40 PSID
30" HgVac — 30 PSI
30" HgVac — 180 PSI
J21K-140
J21K-150
One SPDT output, phosphor bronze bellows, 1/4" NPTF brass process conn.
0-25 PSID
0-90 PSID
0.6-1.0
2.0-4.0
25 PSID
90 PSID
30" HgVac — 110 PSID
30" HgVac — 200 PSID
J21K-232
J21K-254
One SPDT output, 316 SS bellows, 1/4" NPTF process connection
0-70 PSID 2.0-4.0 70 PSID 30" HgVac — 350 PSI J21K-357
One SPDT output, wetted 316 SS bellows, 1/4" process connection
0-6 PSI
0-40 PSI
0.1-0.4
0.3-0.7
6 PSID
40 PSID
30" HgVac — 30 PSI
30" HgVac — 180 PSI
J21K-S140B
J21K-S150B

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