LS200 Series

Liquid Level Switches

Designed for harsh gas compressor scrubber applications, the LS200 Series Liquid Level Switches feature a robust design that trips on rising liquid level only.

  • Electric and pneumatic models available
  • All models screw directly into the scrubber or can be mounted via external float chamber
  • Nickel-plated body to provide enhanced corrosion protection
  • Stainless Steel models available for corrosive atmospheres

FW Murphy Production Controls offers support for all our products. If you are unable to find the product that you need, please call us at 918-957-1000.

  • Overview
  • Specifications
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With both electric and pneumatic models available, the instruments screw directly into the vessel or can be mounted via an external float chamber. The nickel-plated body provides enhanced corrosion protection while the 304 stainless steel float operates in 0.55 specific gravity and heavier fluids. Additional features include:

  • Rated for 2000 psi (13.8 MPa) [138 bar] working pressure
  • Listed for Class I, Div. 1, Grp. C & D locations
  • Canadian registered
  • Stainless steel models available for corrosive atmospheres

The LS200 Series replaces the FW Murphy Series L1200 Liquid Level Switches. The MSLS (Scrubber Level System) replaces the LS200 high-level shut-down switch with the MLS-020 magnetic level switch.

LS200 Liquid Level Switches with 2 in. NPT mounting are float activated to operate an electrical SPDT snap-switch (optional DPDT on some models) for alarm or shutdown of an engine or electric motor. The LS200 connects directly into the vessel wall and can be used with an FW Murphy weld collar or FW Murphy external float chamber.

LS200NDVOR is a float-activated, pneumatic-vent level device used to operate DVU Series dump valves or similar devices. It provides a 2 in. NPT mounting with a pneumatic output for interfacing with pneumatic devices such as the FW Murphy pneumatic dump valve or other pneumatic instrumentation.

LS200NDVO is the Dump Valve Operator (DVO) without the pressure regulator for those applications where the system provides a filter regulator for instrument-quality air or gas as the control medium.

LS200N is the pneumatic level switch without the DVO or filter regulator. Please note: pneumatic media devices require clean, dry, instrument-quality air or gas.

All Models

  • Body: Nickel-plated; optional 316 stainless steel
  • Float: 304 stainless steel
  • Pressure Rating: 2000psig (13.8 MPa) [138 bar]
  • Canadian Registration Numbers (issued by ABSA): 
    • LS200:  0F01476.2
    • L1200, L1200N and L1100 Series:  0F01476.0


  • O-ring: Viton
  • Process Connection: 2” NPT
  • Temperature Rating: -20° to 300°F (-29° to 149°C)
  • Electrical: SPDT std.
  • Wiring: 18 AWG x 36 in. (1.0 mm2 x 916 mm)


  • Process Connection: 2 in. NPT
  • DVO Valve: 3-way N.C. w/manual operator, all connections 1/8 in. NPT (minimum 30 psig required)
  • Filter/Pressure Regulator Set: 
    • Regulator: 0 to 75 psig (0 to 517 kPa) [0 to 5.17 bar] range
    • Maximum Input Pressure: 300 psig (2.07 MPa) [20.7 bar]


  • Process Connection: 2 in. NPT
  • DVO Valve: 3-way N.C. w/manual operator, all connections 1/8 in. NPT


  • Process Connection: 2 in. NPT
  • Vent Valve: 2-way N.C. w/ 1/16 in. (2 mm) orifice and Viton seat; Inlet: 1/8 in. NPT; Outlet: 3/8 in. NPT

Dimensions LS200

Dimensions LS200

Dimensions LS200N, LS200NDVO and LS200NDVOR

With Dump Valve Operator, Pressure Regulator & Gage

Dimensions LS200N, LS200NDVO and LS200NDVOR