Liquiphant T FTL31

Summary

Product identification

• Product: Liquiphant FTL31
• Type: Point level switch for liquids
• Manufacturer: Endress+Hauser
• Document: TI01147F/00/EN/04.21

Application

The Liquiphant FTL31 is a point level switch used in tanks, vessels, and pipes for applications such as overfill protection and pump protection in various systems. It is suitable for use where float switches or conductive, capacitance, and optical sensors are typically employed, but it also performs in challenging conditions like those with conductivity issues, buildup, turbulence, specific flow conditions, or air bubbles.

It is not suitable for hazardous areas. For hygiene areas, the Liquiphant FTL33 is recommended.

Operating limits

• Process temperature range:
  • –40 to +100 °C (–40 to +212 °F)
  • –40 to +150 °C (–40 to +302 °F)
• Process pressure range: Max. –1 to +40 bar (–14.5 to +580 psi)
• Ambient temperature range: –40 to +70 °C (–40 to +158 °F)
• Storage temperature: –40 to +85 °C (–40 to +185 °F)
• Altitude: Up to 2,000 m (6,600 ft) above sea level

Feed water

• Density: > 0.7 g/cm³ (optionally available: > 0.5 g/cm³)
• Viscosity: 1 to 10,000 mPa·s (dynamic viscosity)
• Solids contents: Particle size ø < 5 mm (0.2 in)

Product water

Not applicable to this product.

Electrical

• Electronic Versions & Supply Voltage:
  • 3-wire DC-PNP: 10 to 30 V DC
  • 2-wire AC/DC: 20 to 253 VAC/DC
• Power Consumption:
  • DC-PNP: < 975 mW
  • AC/DC: < 850 mW
• Current Consumption:
  • DC-PNP: < 15 mA
  • AC/DC: < 3.8 mA
• Switching Capacity:
  • DC-PNP: 200 mA
  • AC/DC: 250 mA
• Protection:
  • Reverse polarity protection (integrated for DC-PNP, available for AC/DC)
  • Short-circuit protection (overload protection/short-circuit protection at I > 200 mA for DC-PNP; load check for AC/DC)
• Overvoltage protection: Category II

Mechanical / hydraulic

• Housing Material: Stainless steel (316L)
• Tuning Fork Material: 316L
• Degree of Protection:
  • IP65/67 NEMA Type 4X Enclosure (M12 plug)
  • IP66/68/69 NEMA Type 4X/6P Enclosure (M12 plug for metal housing cover)
  • IP65 NEMA Type 4X Enclosure (valve plug)
  • IP66/68 NEMA Type 4X/6P Enclosure (cable)
• Process Connections: Various threads available, including G ½", G ¾", G 1", MNPT ½", MNPT ¾", MNPT 1", R ½", R ¾", R 1". Weld-in adapters are also available.
• Lateral loading capacity: Maximum 200 N
• Weight:
  • Compact version with G ½" process adapter and valve plug (up to 100 °C): Approx. 140 g (4.938 oz)
  • Short tube version with G ½" process adapter and valve plug (up to 150 °C): Approx. 169 g (5.961 oz)
• Surface Roughness: Metallic surface in contact with process: Ra ≤ 3.2 µm (126 µin)

Performance characteristics

• Switch point: 13 mm (0.51 in) ±1 mm
• Hysteresis: Max. 3 mm (0.12 in)
• Non-repeatability: ±1 mm (0.04 in)
• Switching delay:
  • 0.5 s (tuning fork covered)
  • 1.0 s (tuning fork uncovered)
  • Optional: 0.2 s, 1.5 s, or 5 s
• Switch-on delay: Max. 3 s
• Measuring frequency: Approx. 1100 Hz in air
• Measured error: ±2 mm (0.08 in) in case of device change

Operability

• LED display: Green (operational), Yellow (sensor state/switching state), Red (warning/fault)
• Function test: External function test is possible with a test magnet.

Certificates and approvals

Includes CE mark, EAC conformity, RCM-Tick marking, CSA C/US General Purpose, WHG (overfill/leak detection), Marine approvals (GL, DNV, ABS, LR, BV), CRN approval, and optional inspection certificates (e.g., EN 10204-3.1).

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror