Product Overview

The Magnetic Level Gauge LM400 Series is a reliable liquid level measurement instrument designed for continuous level indication in storage tanks, pressure vessels, and process containers. It consists of a measuring chamber, magnetic float, indicator column with red/white magnetic flags, and flange connections.

Using a magnetic coupling principle, the LM400 provides clear local level indication without direct contact between the process medium and the indicator, making it suitable for corrosive, high-temperature, high-pressure, explosion-proof, and sanitary applications.

It can also be integrated with level switches and 4–20 mA transmitters for remote monitoring and process automation.

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Working Principle

The Magnetic Level Gauge LM400 Series operates using a magnetic float coupling system.

As the liquid level rises or falls, the magnetic float moves inside the measuring chamber. The magnetic field rotates the red/white indicator flags by 180°, providing a highly visible indication of the liquid level.

Optional magnetic level switches and transmitters detect the float position to generate:

• Local visual indication
• High/low level alarms
• 4–20 mA continuous level output
• Remote monitoring and PLC/DCS integration

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Key Features

• Continuous liquid level indication with no blind zones
• Magnetic coupling design isolates the process medium from the indicator
• Suitable for corrosive, high-temperature, and high-pressure applications
• Available in stainless steel, PTFE-lined, and other corrosion-resistant materials
• Optional SPDT level switches for high/low alarms
• Optional 4–20 mA transmitter with HART communication
• Explosion-proof versions available
• Maintenance-free mechanical indication
• Easy installation and long service life

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Technical Specifications

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Applications

The Magnetic Level Gauge LM400 Series is widely used for liquid level monitoring in:

• Chemical processing plants
• Petrochemical facilities
• Oil & gas storage tanks
• Power plant boilers
• Water and wastewater treatment
• Food and beverage processing
• Pharmaceutical production
• Acid and alkali storage tanks
• Cryogenic liquid systems
• Industrial process vessels

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Installation Guidelines

For optimal performance:

• Install the gauge vertically (within ±3°).
• Ensure the process liquid density is at least 0.45 g/cm³.
• Avoid installing near strong magnetic fields.
• Select appropriate materials based on the process medium and operating conditions.
• Verify flange connections are properly sealed before operation.

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Frequently Asked Questions (FAQ)

What is a magnetic level gauge?

A magnetic level gauge is a liquid level indicator that uses a magnetic float and external indicator flags to display liquid levels continuously without direct contact between the process medium and the display.

How does a magnetic level gauge work?

A magnetic float moves with the liquid level inside the chamber. Its magnetic field rotates the external indicator flags and can also actuate level switches or transmitters for remote monitoring.

Can the LM400 be used in hazardous areas?

Yes. Explosion-proof versions are available for hazardous industrial environments.

Can it provide remote level monitoring?

Yes. Optional 4–20 mA transmitters with HART communication and magnetic level switches enable integration with PLC, DCS, and SCADA systems.

What liquids can be measured?

The LM400 is suitable for water, chemicals, acids, alkalis, petroleum products, cryogenic liquids, food-grade liquids, and many other compatible media.

What materials are available?

The gauge can be supplied in stainless steel, PTFE-lined construction, and other corrosion-resistant alloys depending on the application.

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Typical Application Cases

Chemical Storage Tanks

Used to continuously monitor the level of acids, alkalis, solvents, and other corrosive chemicals in storage tanks. The isolated magnetic indication prevents media leakage while providing reliable local and remote level monitoring.

Typical Media

• Sulfuric acid
• Hydrochloric acid
• Sodium hydroxide
• Methanol
• Ethanol
• Organic solvents

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Petrochemical Process Vessels

Installed on reactors, separators, and buffer tanks to monitor liquid levels under high pressure and high temperature. Explosion-proof versions ensure safe operation in hazardous areas.

Typical Equipment

• Crude oil tanks
• Fuel storage tanks
• Process separators
• Distillation columns
• Condensate tanks

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Boiler and Power Plant Systems

Suitable for boiler drums, condensate tanks, deaerators, and feedwater systems where stable liquid level monitoring is critical for safe operation.

Typical Applications

• Boiler drum level indication
• Condensate recovery systems
• Steam generation equipment
• Thermal power plants

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Water & Wastewater Treatment

Used for chemical dosing tanks, clean water reservoirs, sludge tanks, and wastewater treatment systems to provide continuous level indication and pump control.

Typical Applications

• PAC dosing tanks
• Sodium hypochlorite tanks
• Lime slurry tanks
• Wastewater storage tanks
• Clean water tanks

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Food & Beverage Industry

Manufactured with stainless steel materials suitable for hygienic processes involving edible liquids where reliable and contamination-free level monitoring is required.

Typical Media

• Milk
• Syrup
• Edible oil
• Beverage ingredients
• Liquid sugar

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Pharmaceutical Industry

Used for sterile process tanks and storage vessels requiring reliable level monitoring without direct contact between the indicating mechanism and the process fluid.

Typical Applications

• Pharmaceutical reactors
• Purified water tanks
• Ethanol storage
• API processing vessels

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Cryogenic Liquid Storage

Designed for extremely low-temperature applications using special float materials and construction.

Typical Media

• Liquid nitrogen (LN₂)
• Liquid oxygen (LOX)
• Liquid argon (LAr)
• LNG

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Oil & Gas Industry

Provides continuous level indication for lubricating oil, diesel, crude oil, and other petroleum products while supporting explosion-proof installation requirements.

Typical Equipment

• Fuel tanks
• Lubrication systems
• Diesel storage tanks
• Offshore process equipment

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OEM Equipment Integration

Widely integrated into skid-mounted equipment and industrial automation systems for local indication, alarm control, and remote signal transmission.

Typical Equipment

• Chemical dosing skids
• Water treatment skids
• Heat exchange systems
• Hydraulic oil stations
• Process automation equipment

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Why Choose the Magnetic Level Gauge LM400 ?

• Reliable operation under high pressure and high temperature
• Suitable for corrosive, toxic, and hazardous liquids
• No glass tube, reducing leakage and breakage risks
• Clear visual indication with optional remote monitoring
• Compatible with alarm switches and 4–20 mA transmitters
• Available in explosion-proof and corrosion-resistant versions
• Ideal for continuous tank level measurement in demanding industrial environments