Jerguson® External Cage Float Operated Magnetic Level Switch

Jerguson® products are also available under the Magne-Sonics® brand as required based on approved vendor specifications.

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• Tri-Magnet Switching
• Vibration Resistant
• Weatherproof
• Flameproof
• Sealed (shown) or Flanged Cage Body
• 316 SS Trim
• ASME B31.1/B31.3 Design
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The float drives a stainless steel sheathed permanent magnet attached to the float rod in the glandless pressure tube.  As the float rises and falls with a changing liquid level the float assembly moves upwards inside the pressure tube.

A switch mechanism is mounted inside the enclosure adjacent to the pressure tube, and is activated by the rising or falling magnet.

The vertical movement of the float magnet in the pressure tube simultaneously actuates the secondary and switch magnets within the switch mechanism, to operate the contacts.  This “three-magnet” system enables the float magnet to pass the switch and actuate switch mechanisms at other levels.  Switch mechanisms which are actuated will not reset until the float magnet actuates the switch mechanism on a falling level.

Switching is achieved with the unique tri-magnet snap-action switch system.




The following video depicts the benefits of the Tri-Magnet level switch system compared to a standard micro-switch or mercury-switch mechanism in external cage level switches:



Brochure: External Cage Float Operated Magnetic Level Switch Brochure

IOM: External Cage Float Installation, Operation and Maintenance Manual