Liquicap T FMI21

Summary

Product Identification

• Product Name: Liquicap T FMI21
• Product Type: Capacitive level measurement sensor
• Description: Two-rod probe for continuous measurement in conductive liquids.

Application

The Liquicap T sensor is designed for continuous level measurement in conductive liquids with a minimum conductivity of 30 μS/cm. It is preconfigured from the factory for 0% to 100% of the ordered probe length. The measurement is independent of the liquid's dielectric constant at conductivities of 30 μS/cm or higher.

Key applications include:

• Small measuring ranges (starting from 150 mm)
• Cistern measurements
• Aggressive liquids (acids, alkalis)
• Use with various tank materials (plastic, stainless steel, concrete) and tank shapes.
• Can be deployed in Ex area, Zone 2.

When used with the Fieldgate FXA320, it facilitates remote measured value interrogation for inventory management and logistics optimization.

Operating Medium

• Minimum Conductivity: ≥ 30 μS/cm
• Viscosity: Maximum 2000 cSt
• Independence: Measurement is independent of the dielectric constant (dc-value) and conductivity of the liquid above 30 μS/cm.

Measuring Range

• Probe Length: 150 mm to 2500 mm
• Adjustable Initial Capacitance (CA): 0 to 2000 pF
• Permitted Span (ΔC): 25 to 2000 pF
• End Capacitance (CE): Maximum 2100 pF
• Measuring Frequency: 250 kHz

Output

• Electronic Insert: FEI20 (4...20 mA)
• Output Signal: 3.8...20.5 mA
• Switch-on Current: Maximum 20 mA (< 500 ms)
• Signal on Alarm: > 21 mA

Power Supply

• Connection Voltage (FEI20): 10 to 30 V DC
• Reverse Polarity Protection: Integrated
• Power Consumption: < 0.7 W
• Current Consumption: < 22 mA

Mechanical Construction

• Process Connection: G 1½ or NPT 1½
• Probe Rods:
  • Material: 1.4404/316L or optional carbon fibre (CFC) for aggressive acids.
  • Diameter (without insulation): 4 mm
  • Maximum Length: 2500 mm
  • Minimum Length: 150 mm
  • Insulation Thickness: 0.5 mm
• Housing (F16):
  • Housing Material: PBT-FR
  • Cover Material: PBT (optional sight glass: PA)
• Weight: 600 g (for 1 m rod length)

Environment

• Ambient Temperature Range (Electronic): -40 to 70 °C
• Ambient Temperature Limits: -40 to 80 °C (accuracy restricted in the limit range)
• Storage Temperature: -40 to 80 °C
• Climate Class: Suitable for the tropics as per DIN IEC 68 Part 2-38
• Degree of Protection: IP66
• Shock Resistance: 30 g (DIN EN 60068-2-27 / IEC 68-2-27)
• Vibration Resistance: 20 to 2000 Hz, 1 (m/s²)²/Hz (with min. rod length 150 mm)

Process Limits

• Process Pressure: –1 to 10 bar

Electrical

• Cable Entries: M 20x1.5 or NPT ½
• Cable Cross-section: Maximum 2.5 mm² (including ferrule)
• Electromagnetic Compatibility:
  • Interference emission to EN 61326, Class B
  • Interference immunity to EN 61326, Annex A (Industrial)

Certificates and Approvals

• CE Mark: Confirms conformity with EC Directives.
• Overfill Protection: WHG-approved (German Water Resources Law).
• Ex Approval: ATEX II 3 G EEx nA IIC T6 (non-sparking equipment).
• Other Approvals: CSA/US General Purpose.

Documentation

Refer to www.endress.com for available documentation, including:

• Technical Information sheets for related products (Fieldgate FXA320, transmitters, power supply units).
• Operating Instructions.
• Certificates (WHG, ATEX).

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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