Murphy LM300 Level Switch

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. 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.

Technical Data

Available on backorder

Request quotation and delivery time

Description
Additional information

Description

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

Additional information

Weight	3.4 kg
Specifications	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) Max. 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 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.

Weight

3.4 kg

Specifications

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) Max. 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 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.