Endress+Hauser Liquiphant FTL51B – Safe and Reliable Point Level Switch for Liquids

The Liquiphant FTL51B is a versatile vibronic point level switch designed for reliable level detection of all types of liquids in process industries. Based on Endress+Hauser’s proven vibration technology, it provides dependable switching performance even under changing process conditions such as foam, turbulence, gas bubbles, flow or product buildup.

Designed for demanding industrial applications, the FTL51B combines robust mechanical construction, advanced diagnostics and safety functions, making it an ideal solution for overfill protection, pump dry-run protection and safety-related level monitoring.

Universal Vibronic Technology for Liquid Level Detection

The Liquiphant FTL51B uses a vibrating tuning fork principle to detect whether the sensor is covered by liquid. Unlike technologies that depend strongly on media characteristics, the vibronic measuring principle provides stable switching performance without requiring frequent recalibration.

Key performance:

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  Measuring principle: Vibronic vibration technology
  
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  Application: Point level detection for liquids
  
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  Minimum medium density: 0.5 g/cm³ (0.4 g/cm³ optional)
  
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  Process temperature: –50 to +150 °C
  
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  Process pressure: Vacuum to 100 bar
  
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  Wetted materials: 316L stainless steel / Alloy
  
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  Sensor length: Up to 6 m
  
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  Communication: HART, Bluetooth, NAMUR, PFM, relay and other switching outputs
  
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  Safety functions: SIL2 / SIL3 according to IEC 61508
  
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  Diagnostics: Heartbeat Technology
  

Designed for Safety-Critical Applications

The FTL51B is developed according to IEC 61508 and supports SIL2 and SIL3 applications, making it suitable for safety-related level monitoring tasks.

For overfill protection applications, the device supports WHG approval and guided proof testing. Users can perform verification procedures through intuitive workflows, helping simplify safety checks and documentation.

Typical safety applications include:

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  Tank overfill protection
  
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  Pump dry-run protection
  
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  High and low level alarms
  
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  Safety instrumented systems (SIS)
  
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  Hazardous area installations
  

Reliable Measurement Without Influence from Process Conditions

One of the major advantages of the Liquiphant FTL51B is its ability to maintain reliable switching performance despite challenging process conditions.

The sensor is not significantly affected by:

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  Changing liquid properties
  
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  Foam formation
  
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  Gas bubbles
  
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  Turbulent flow
  
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  Product buildup
  
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  Vibrations
  

This makes it suitable for a wide range of liquids, including challenging industrial media.

Flexible Installation and Process Connections

The FTL51B features a modular design concept with multiple process connection options, allowing adaptation to different tanks, vessels and pipelines.

Available configurations include:

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  Threaded connections
  
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  Flange connections
  
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  Hygienic Tri-Clamp connections
  
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  Optional extension tube up to 6 m
  

The robust 316L or Alloy wetted materials provide excellent compatibility with various industrial process media.

Digital Communication and Smart Maintenance

The Liquiphant FTL51B supports modern digital communication options including HART and Bluetooth wireless technology.

Bluetooth connectivity enables convenient commissioning and maintenance using the SmartBlue App, while digital device information supports efficient asset management.

Additional features include:

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  Bluetooth operation
  
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  RFID identification tag
  
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  LED status module
  
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  Heartbeat diagnostics
  
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  Plug-and-play commissioning
  

Heartbeat Technology for Continuous Diagnostics

With integrated Heartbeat Technology, the FTL51B provides advanced diagnostic capabilities and simplified verification without interrupting the process.

This helps users improve maintenance planning, increase plant availability and gain better visibility into device condition.

Suitable for Wide Industrial Applications

The Liquiphant FTL51B is widely used across process industries where reliable point level detection is required.

Typical applications include:

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  Chemical storage tanks
  
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  Oil and gas processing
  
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  Power generation
  
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  Water treatment
  
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  Pharmaceutical processes
  
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  Food and beverage applications
  
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  Hazardous area applications
  

Frequently Asked Questions

What is the Liquiphant FTL51B used for?

The FTL51B is used for point level detection of liquids, including overfill protection, pump protection and safety-related level monitoring.

What measuring principle does the FTL51B use?

The FTL51B uses a proven vibronic vibration measuring principle with a tuning fork sensor.

Can the FTL51B handle changing liquid conditions?

Yes. The sensor is designed to operate reliably even with changing media properties, foam, gas bubbles, turbulence and buildup.

What is the maximum process temperature of the FTL51B?

The FTL51B supports process temperatures from –50 to +150 °C.

What is the maximum pressure rating?

The maximum process pressure is 100 bar.

Does the FTL51B support SIL applications?

Yes. The device supports SIL2/SIL3 applications according to IEC 61508.

What communication options are available?

Depending on configuration, the FTL51B supports HART, Bluetooth, NAMUR, PFM and switching outputs.