120 Series

SIL2-certified switch for explosion-proof pressure, vacuum, differential pressure, and temperature applications

As safety requirements become more stringent, the determining factor in specifying an industrial pressure, differential pressure, and/or temperature SIL2-certified switch rests upon that switch protecting equipment, processes, and personnel. Meeting hazardous location requirements through worldwide approvals and certifications, UE’s 120 Series is the choice where potentially explosive or highly corrosive atmospheres exist.

The 120 Series SIL2-certified switch offers a variety of pressure, vacuum, differential pressure, and temperature ranges, as well as process connections, wetted materials, and sensor types. With a common flexible platform, models can quickly be adapted at the factory for special requirements such as ranges, process connections, and electrical ratings. Typical industries using the 120 Series SIL-certified switch include chemical, petrochemical, refinery, oil and gas production and transmission, and pharmaceuticals.


  • SIL2-certified switch
  • Class 1, Divisions 1 & 2, Zone 1
  • UL listed, cUL-certified, ATEX flame-proof & CE (LVD, PED)-compliant; other worldwide hazardous location approvals available
  • Dual electrical conduit openings provide mounting flexibility while terminal block provides ease of wiring
  • SPDT, DPDT, or dual SPDT switch output
  • Pressure sensor materials, including welded stainless-steel diaphragms and bellows
  • Internal or external setpoint adjustment
  • Heat trace and freeze protection temperature models
  • Adjustable setpoint ranges:
    • Pressure and vacuum: 30 “Hg Vac to 6000 psi
      -1 to 414 bar
    • Water Column: 300 “wc Vac to 250 “wc
      -746,7 to 622,3 mbar
    • Differential Pressure: 0.2 “wcd to 500 psid
      0,5 mbar to 34,5 bar
    • Temperature: -120° F to 650° F -85° C to 343.3° C


Visit our Certifications Page for all 120 series Certifications

  • Standard product approvals include cULus, ATEX, and IECEx
  • Optional approvals for Russia, Ukraine, China, Brazil, and Korea
  • Internal adjustment hex or external adjustment via calibrated dial(s) with tamper-resistant cover
  • Integral cover lock
  • SPDT, DPDT, or dual SPDT output
  • Wide variety of sensor materials
  • Optional Hastelloy® and Monel® sensor materials for corrosive media
  • Wide adjustable deadband models
  • Flush-mount sensors
  • Heat-tracing temperature models
  • Most models available for immediate delivery!

Installations Manuals


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