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High-pressure external cage liquid level switch

High Pressure Liquid Level Switches are displacer actuated units, utilizing a single switch mechanism for level alarm or control functions. These units are designed for service pressures up to 5000 psig (345 bar) and liquids with specific gravities of 0.40 and above.

High-pressure external cage liquid level switch
Technology

External cage switches

A permanent magnet is attached to a pivoted switch actuator. As the float/displacer rises following the liquid level, it raises the attraction sleeve into the field of the magnet, which then snaps against the non-magnetic enclosing tube, actuating the switch. The enclosing tube provides a static pressure boundary between the switch mechanism and the process. On a falling level, the float/displacer deactivates the switch.

Features

  • Fabricated carbon steel cages
  • Model B74 available with 304 or 316 stainless steel cages as standard
  • Inconel displacer spring and stainless steel trim
  • Stainless steel displacers
  • Sealed or flanged cages
  • Pressures to 5000 psig (345 bar)
  • Temperatures to +750 °F (+400 °C)
  • Specific gravity as low as 0.40

Options

  • Special levels/body extensions
  • 316 and 304 stainless steel chambers
  • NACE construction
  • Gold switch contacts
  • Interface detection
  • Vent and drain connections

Operating principle

Liquid level movement changes the buoyancy force on a displacer suspended from a range spring. The force change on the spring causes it to extend or compress, moving an attraction sleeve into or out of the field of the switch magnet, actuating the switch.

External Cage
External Cage

Approvals

XP=Explosion Proof, IS=Intrinsically Safe, NI=Non-Incendive, NS=Non-Sparking, ELV=EMC/Low Voltage

ATEX Ex d, Ex ia
CCOE Ex d
CSA XP
FM XP
EAC (GOST) Ex d, Ex ia
IEC Ex d
Inmetro Ex d
Korea Ex d
NEPSI Ex d
SIL SIL 2 (1oo1)

Other approvals are available. Consult factory for more details.

Downloads

Approvals & certificates

ATEX Ex d certificate Mechanicals
ATEX Ex i certificate Mechanicals
Canadian certificate Mechanical Switches - IS, NI
FM certificate Mechanical Switches
FMEDA Report Flanged Sealed Cages
IECEx d certificate Mechanicals

Instruction manuals

High Pressure Series H13, H31 & H51 I&O Manual
Series H13, H31 & H51 Cage mounted displacer level switches
High Pressure Series N15, N32 & N52 I&O Manual
Series N15, N32 & N52 Cage mounted displacer level switches

Product catalogs

High Pressure External Caged Liquid Level Switches
High Pressure Liquid Level Switches are displacer actuated units, utilizing a single switch mechanism for level alarm or...

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