Endress+Hauser Liquiphant FTL31 – Vibronic Point Level Switch

The Liquiphant FTL31 is a compact vibronic point level switch for liquids, designed for reliable level detection in industrial applications. Its stainless steel housing and compact construction make it suitable for installations where space is limited and dependable point level switching is required.

Unlike continuous level transmitters, the FTL31 is designed to detect whether liquid has reached a defined switching point. Typical applications include overfill protection and pump dry-run protection, particularly in cleaning systems and machinery applications.

Reliable Point Level Detection Without Calibration

The FTL31 uses vibronic technology to detect the presence or absence of liquid at the sensor. One of its key advantages is that switching is largely independent of the properties of the measured medium.

The instrument requires no calibration, helping simplify installation and commissioning. Plug-and-play operation and continuous self-monitoring further support straightforward operation.

Key Advantages

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  Vibronic point level detection
  
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  Designed for liquids
  
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  No calibration required
  
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  Switching independent of many changing media properties
  
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  Continuous self-monitoring
  
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  Compact stainless steel housing
  
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  IO-Link connectivity for convenient parameter setting
  
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  Suitable for overfill protection
  
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  Suitable for pump dry-run protection
  
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  Process temperature up to 150 °C
  
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  Process pressure up to 40 bar
  
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  Minimum medium density >0.7 g/cm³, with an optional version down to >0.5 g/cm³
  
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  Threaded process connections
  
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  WHG overfill protection and leakage detection options
  
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  Marine approvals available depending on configuration
  

Compact Design for Industrial Applications

The FTL31 is designed as a particularly compact member of the Liquiphant family. Its compact stainless steel construction makes it suitable for small tanks, machinery, cleaning systems and installations where mounting space is restricted.

The device uses threaded process connections and is intended for general industrial applications, with machinery applications being one of its main areas of use.

Suitable for Overfill and Pump Protection

Point level switches are often used as an additional layer of process protection rather than as a continuous measurement device.

The FTL31 can be installed at a defined high-level point to provide overfill protection, or at a low-level point to help prevent pump dry running.

This makes it useful in applications where a simple, reliable switching signal is more appropriate than a continuous level value.

IO-Link for Easy Parameter Setting

The IO-Link capability of the FTL31 provides digital communication for convenient parameter setting and device integration.

This can simplify commissioning and make the sensor easier to integrate into modern machine and automation architectures compared with a basic switching device.

Designed for Demanding Process Conditions

The FTL31 supports a process temperature range of -40 to +150 °C and process pressure from vacuum up to 40 bar.

The standard minimum medium density is greater than 0.7 g/cm³, while an optional configuration can detect media with density above 0.5 g/cm³.

The device also offers protection and certification options for applications requiring overfill protection, leakage detection and hazardous-area approvals, depending on the selected configuration.

Main Technical Parameters

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  Measurement principle: Vibronic
  
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  Measurement type: Point level detection
  
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  Application: Liquids
  
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  Process temperature: -40 to +150 °C
  
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  Process pressure: Vacuum to +40 bar
  
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  Minimum medium density: >0.7 g/cm³
  
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  Optional minimum density: >0.5 g/cm³
  
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  Process connections: Threads
  
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  Housing: Stainless steel
  
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  Communication: IO-Link available
  
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  Application functions: Overfill protection and pump dry-run protection
  
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  Diagnostics: Continuous self-monitoring
  
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  Calibration: No calibration required
  
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  Surface roughness: 3.2 µm
  
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  Approvals: WHG, marine and hazardous-area options depending on configuration
  

Typical Applications

The Liquiphant FTL31 is particularly suitable for:

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  Overfill protection
  
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  Pump dry-run protection
  
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  Cleaning systems
  
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  Machine equipment
  
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  Small process tanks
  
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  Liquid storage vessels
  
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  General industrial liquid level detection
  

Its compact design and media-independent vibronic switching make it especially useful where a simple and reliable point level switch is required.

FAQ

What is the Liquiphant FTL31 used for?

The FTL31 is a point level switch for liquids, mainly used for overfill protection and pump dry-run protection.

Is the FTL31 a continuous level transmitter?

No. The FTL31 is a point level switch. It detects whether liquid has reached the defined switching point rather than continuously measuring the liquid level.

Does the FTL31 require calibration?

No. One of the main advantages of the vibronic measurement principle is no calibration requirement, helping simplify commissioning.

What is the maximum process temperature?

The FTL31 can operate at process temperatures from -40 to +150 °C.

What is the maximum process pressure?

The specified process pressure range extends from vacuum to 40 bar.

Can the FTL31 detect different liquid media?

Yes. Vibronic switching is designed to be reliable and largely independent of media properties, reducing the need for individual calibration when the medium changes.

Does the FTL31 support IO-Link?

Yes. IO-Link is available for convenient parameter setting and digital device integration.

Can the FTL31 be used for pump protection?

Yes. The FTL31 is suitable for pump dry-run protection, as well as overfill protection.