Liquiphant M FTL51

Summary

Product identification

• Product Name: Liquiphant M
• Model Number: FTL51C
• Type: Vibronic Point Level Switch

Application

The Liquiphant M is a point level switch designed for the detection of maximum or minimum levels in tanks and pipes containing all types of liquids. It is particularly suitable for aggressive media due to its high corrosion resistance. The device functions reliably irrespective of flow, turbulence, bubbles, foam, vibration, solids content, or buildup.

Operating limits

• Temperature: –50 °C to 150 °C (–58 °F to 302 °F)
• Pressure: up to 40 bar (580 psi)
• Viscosity: up to 10,000 mm²/s (cSt)
• Density: ≥ 0.5 g/cm³ (SGU) or ≥ 0.7 g/cm³ (SGU)

Feed water

• Density: 0.7 g/cm³ (SGU) is the delivery status; 0.5 g/cm³ (SGU) can be adjusted.
• Solids content: ≤ ø5 mm (0.2 in)
• Viscosity: ≤ 10,000 mm²/s (cSt)
• Lateral loading capacity: ≤ 75 Nm

Product water

• Maximum measured error: +/- 1 mm (0.04 in) under reference operating conditions.
• Repeatability: 0.1 mm (0.004 in)
• Hysteresis:
  • ECTFE and PFA: approx. 2 mm (0.08 in)
  • Enamel: approx. 2.5 mm (0.1 in)

Electrical

The Liquiphant M FTL51C is available with several electronic inserts, including:

• FEL51: Two-wire AC version (Supply voltage: AC 19 to 253 V)
• FEL52: Three-wire DC PNP version (Supply voltage: DC 10 to 55 V)
• FEL54: Universal current version with relay output (Supply voltage: AC 19 to 253 V or DC 19 to 55 V)
• FEL55: 8/16 mA signal transmission for separate switching unit (Supply voltage: DC 11 to 36 V)
• FEL56: NAMUR L-H edge signal for separate switching unit (Supply voltage: DC 8.2 V ±20 %)
• FEL58: NAMUR H-L edge signal for separate switching unit (Supply voltage: DC 8.2 V ±20 %)
• FEL57: PFM signal transmission for separate switching unit (Supply voltage: DC 9.5 to 12.5 V)
• FEL50A: PROFIBUS PA digital communication (Bus voltage: DC 9 to 32 V)
• FEL50D: Pulse output for Density Computer FML621 (Frequency range: 300 to 1500 Hz)

Mechanical / hydraulic

• Process connections: Flanges according to DIN/EN, ASME, JIS from DN 40 / 1½".
• Sensor length: Up to 3000 mm (118 in) for synthetic coating, up to 1200 mm (47.2 in) for enamel coating.
• Coating materials: Enamel, PFA Edlon (FDA-approved), ECTFE.
• Housing materials: Polyester, Stainless steel, Aluminum.
• Dimensions: See official PDF for detailed dimensions based on housing type.
• Weights: See official PDF for component weights (basic weight, housings, spacers, flanges, etc.).
• Materials: Wetted parts include extension pipe and tuning fork substrates, with various coating options. See PDF for detailed material specifications.

Environment

• Ambient temperature range: Dependent on medium temperature. See official PDF for graph.
• Storage temperature: –50 to +80 °C (-58 to 176 °F)
• Operating altitude: Up to 2000 m (6600 ft), extendable to 3000 m (9800 ft) with overvoltage protection.
• Degree of protection: IP65, IP66, IP67, IP69 (depending on housing and approval). NEMA 4X, 6P also available.
• Vibration resistance: As per IEC 68, parts 2-6.
• Electromagnetic compatibility: Interference emission and immunity according to EN 61326 and NAMUR Recommendation NE 21.

Certificates and approvals

• CE mark
• RoHS
• RCM-tick mark
• EAC conformity
• CRN approval
• Pressure Equipment Directive 2014/68/EU (PED)
• Process seal according to ANSI/ISA 12.27.01
• Use in hazardous zones (International approvals certify use in hazardous areas).
• Functional safety to SIL2/SIL3 in accordance with IEC 61508/IEC 61511-1.
• FDA-approved material (PFA Edlon) available.
• WHG approval (for overfill prevention) with FEL57 and FEL50A.

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Disclaimer: This summary is based on extracted text and may not include all figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror