Jerguson · Level Switches
Jerguson side-mount level switches: JMRS, JMLS and horizontal float
Float operated level switches mounted horizontally through the vessel wall: JMRS hermetically sealed reed switch (SPST 3 A), JMLS magnetic snap-action switch (SPDT or DPDT, CSA Class I), and the flanged Tri-Magnet horizontal side mounted switch to ASME B31.1 and B31.3.
Side-mount switches go straight through a connection in the vessel wall, with the float inside the tank. They give a contact when the level rises above or falls below the connection, which makes them a simple choice for high and low alarms, overflow and leak detection.
The JMRS is the low cost option: the float brings a magnet close to a hermetically sealed reed switch. Construction is all stainless steel, with no O-rings, packing or diaphragms that could leak. The JMLS uses repelling magnets through a stainless steel barrier for a latching snap action with SPDT or DPDT contacts and an integral conduit box, CSA certified for Class I areas, and also serves cryogenic liquids.
For process and power applications the horizontal side mounted Tri-Magnet switch has a flanged chamber to ASME B31.1 and B31.3, with the same spring-free three-magnet mechanism as the Jerguson external cage switches.
Selection data we need
High or low switch point, medium and specific gravity, design pressure and temperature, process connection size and type, wall thickness or nozzle length, contact type and rating, area classification.
Applications
- High or low level alarms, overflow and leak detection
- Fuels, lube and hydraulic oils, separators and fuel-water interfaces
- Chemicals, food, pharmaceutical liquids and marine bilge and tank levels
- Cryogenic liquids such as methane, nitrogen, carbon dioxide and oxygen (JMLS)
