Search Icon
Home » Products » Compressor » LM300 Series

LM300 Series

Level Maintainers

The LM300 Series Level Maintainer automatically adds oil to the crankcase as needed to keep the lube level normal. Most models have built-in switches that will alarm and/or shut down the equipment if the makeup supply is depleted and engine oil level falls or if overfill conditions exist.

  • Maintains proper lube level
  • Shutdown on low level or high and low level
  • Low level alarm before shutdown
  • Manual float switch test
  • High visibility frog-eye lens
  • Optional pipe or universal mounting brackets
  • Optional inlet orifices for low to high pressure applications
  • Explosion-proof models available

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
  • Diagrams
  • Literature

The LM300 can be used in engines, compressors, pumps and coolers.

The LM300 Series EX models (explosion-proof) are CSA certified for Class I, Division 1 Hazardous areas.

  • Case/Cover: Die cast aluminum
  • Switch Housing: Aluminum
  • Approval Rating: All CSA Certified with switch contacts rated at 10 A at 250 VAC (standard)
    • LM301 through LM305: CSA certified for non-hazardous locations. Enclosure Type 4 certified
    • LM301-EX through LM305-EX: CSA certified for Class I, Groups C and D; Class II, Groups F and G hazardous locations; Enclosure Type 4 certified
  • Float: Rigid polyurethane foam; Polyurethane coated
  • Max. Ambient Temperature: 250° F (121° C)
  • Oil Inlet Connection: Top entry 1/2-14 NPT with built-in filter screen (removable for cleaning)
  • Inlet Orifices: 1/4 in. (6 mm) standard; 1/8 in. (3 mm) available
  • Wire (switch models): 18 AWG x 13 in. (1.0 mm2 x 330 mm)
  •  Maximum Inlet Pressure (MIP):
    • 30 psi (207 kPa) [2.07 bar] with 1/8 in. (3 mm) orifice
    • 15 ft oil (4.6 m oil) with 1/4 in. (6 mm) orifice
  • Max. Differential: 2 in. (51 mm) between running and stationary oil level
  • Max. Case Pressure (MCP): 15 psi (103 kPa) [1.03 bar]
  • Orifice Seal: Buna-N Thumb-Valve
  • Switch Contact: Silver, SPDT snap-acting, rated at 10 A @ 125, 250 VAC; 10 A @ 30 VDC (1 only for low level; 2 only for high and low; or 2 only for low level with alarm before shutdown)
  • Outlet Connection: 3/4-14 NPT left side, right side and bottom
  • Crankcase Balance Vent Fitting: 1/2-14 NPT
  • Mounting: Accepts FW Murphy pipe or universal mounting brackets
  • Lens: Clear frog eye non-staining, high-impact, high-temperature nylon; UV and heat stabilized
  • Glass Lens: Available on LM301 and LM301-EX models. Specify GL as part of model number when ordering
  • Dial: High visibility white background with green and white index lines for normal level indication
  • Test Knob: Rotate to test switch operation. Turn clockwise for low level test and turn counterclockwise for high level test.

Dimensions LM300

 

Dimensions LM300EX

 

Mounting Pipe Bracket Kit

Mounting Universal Bracket Kit