• Most Versatile Level Switch Available
  • Explosion Proof and NEMA 4X Enclosures
  • No Moving Parts Principle
  • 316L Stainless Steel Sensor with Special Alloys Available
  • Temperatures to 900F
  • Field Selectable High or Low Liquid Level
  • Pressures to 10,000 PSIG
  • Threaded, Flanged, Retractable Probes
  • Exotic Alloys for Corrosion Resistance
  • Easy Field Calibration

The LX series level switch is the most versatile instrument ever designed for level control. One unit can be field calibrated to detect the interface of air/foam, foam/liquid, oil/emulsion, emulsion/water, oil/water, and a solid in a liquid. It can also be used as a universal high level switch that will alarm if any type of liquid comes in contact with the probe.


The sensor head employs two temperature sensors with a constant very low power heating source physically attached to one of the temperature sensors (see figure above). The second temperature sensor is isolated from the heating source and provides compensation for changing process temperatures. The probe operates by sensing the thermal conductivity (not electrical conductivity) of the product surrounding the probe. All liquids that form an interface will have a difference in thermal conductivity that can be sensed. With no moving parts exposed to the process users are provided an extremely reliable and repeatable instrument even in extremely viscous or corrosive applications.


Electronics are available with single or dual switch points. The dual switch point option allows one sensor to detect two different interfaces or one interface and another process variable such as fluid agitation. Temperature monitoring is also available with either a switch output or a linear 4-20 mA output. Relay outputs are standard and are offered with several different configurations and contact ratings. Remote mounting of the electronics is also available and is recommended for high temperature applications and hard to reach locations.

  • Tank Level Switches
  • Wet/Dry: Point sensor detects high and or low level of practically any liquid.
  • Liquid to Liquid Interface: Detects any liquid to liquid interface
  • Agitation Monitor: Detects the difference between agitated and non-agitated liquids or slurries.
  • Overflow/Drain line Sensor: Capable of detecting liquid in partially filled lines.
  • Emulsion Detector: Emulsions typically can be detected from their base liquids.
  • Solids in Liquids: Detects solids surrounding sensor probe in settling tank applications.
  • Redundant/diversified Level Indicator: Provides primary or secondary high or low level alarms to meet critical applications that require redundant/diversified technologies.
  • Universal Level Switch: Detects liquids in low or high levels applications regardless of fluid dielectric properties.
  • Foam Detector: Differentiates differences between foam and liquids or foam and gases.
  • Flood alarm: Can be mounted in overflow collection basins to alarm when liquid is present. As little as ⅛” of liquid can be detected.
  • Retractable Probe Mounting: Retractable probe mounting is available for an adjustable detection point in top mounted applications