Prosonic S FDU95

Summary

Product identification

Prosonic S FDU95 Ultrasonic sensor for level and flow measurement.

Application

• Continuous, non-contact level measurement of liquids and bulk solids in silos, on conveyor belts, in material stockpiles and in crushers.
• Flow measurement in open flumes and measuring weirs.
• Maximum measuring range: 45 m (148 ft) in bulk solids.

Benefits

• Integrated temperature sensor for time-of-flight correction.
• Hermetically welded PVDF sensor for maximum chemical resistance.
• Suitable for harsh ambient conditions with separate transmitter installation (up to 300 m / 984 ft).
• Self-cleaning effect minimizes deposit build-up.
• Weather resistant and flood-proof (IP68).
• International Dust-Ex and Gas-Ex certificates available.

Technical Data

Input

• Blocking distance:

  • FDU95-#2###: 0.9 m (3.0 ft)
  • FDU95-#1###: 0.7 m (2.3 ft)

• Measuring range: Effective sensor range depends on operating conditions. Attenuation values from surface conditions, dust, filling curtains, and temperature differences contribute to the total attenuation, which impacts the range. See the provided range chart for calculations.

• Operating frequency:

  • FDU95-1**: 17 kHz
  • FDU95-2**: 18 kHz

Power supply

• Supply voltage is provided by the transmitter.

Electrical connection

• Grounding: Connect the yellow/green protective conductor (GNYE) of the sensor to local potential equalization after a maximum distance of 30 m (98 ft).
• Interference: Avoid routing sensor cables parallel to high-voltage power lines or near frequency converters.
• Cable shield: Connect the black wire (shield) to the "BK" terminal. For extension cables, twist the shield and connect to the "BK" terminal.

Extension cable specifications

• Maximum total length (sensor cable + extension cable): 300 m (984 ft).
• Number of wires: As per connection diagram.
• Shielding: One shielding braid for the YE wire and one for the RD wire.
• Cross-section: 0.75 to 2.5 mm² (18 to 14 AWG).
• Resistance: Max. 8 Ω per wire.
• Capacitance, wire to shield: Max. 60 nF.
• Protective ground: May not be within the shielding.

Installation

• Level measurement:

  • Recommended distance to vessel wall: 1/6 of vessel diameter.
  • Avoid mounting in the center of the vessel.
  • Avoid measurements through the filling curtain.
  • Ensure no internal fixtures are in the signal beam.
  • For bulk solids, use the FAU40 alignment unit to align the sensor perpendicular to the surface.
  • The lower edge of the sensor should be inside the vessel.
  • Maximum level must not enter the blocking distance.

• Flow measurement:

  • Mount sensor upstream above the maximum upstream level (Hmax) plus the blocking distance (BD).
  • Position sensor in the center of the channel or weir.
  • Align sensor perpendicular to the surface of the liquid.
  • Observe mounting distance to flume constriction or weir edge.
  • Protect sensor against sun and precipitation using a weather protection cover.

Environment

• Degree of protection: IP68 / NEMA6P (tested for 24 h at 1.83 m (6 ft) underwater).
• Vibration resistance: DIN EN 600068-2-64; 20 to 2000 Hz; 1 (m/s²)²/Hz; 3x100 min.
• Storage temperature: Identical to process temperature.
• Thermal shock resistance: Based on DIN EN 60068-2-14.
• Electromagnetic compatibility: Complies with EN 61326 series and NAMUR Recommendation EMC (NE 21). Meets requirements of class A for interference emission; designed for industrial environments.

Process

• Process temperature:

  • FDU95-1**: –40 to +80 °C (–40 to +176 °F)
  • FDU95-2**:
    • Non-Ex: –40 to +150 °C (–40 to +302 °F)
    • Dust-Ex: –40 to +130 °C (–40 to +266 °F)

• Process pressure: 0.7 to 1.5 bar (10.15 to 22 psi).

Mechanical construction

• Dimensions: See diagram.
• Weight: Approx. 4.5 kg (9.92 lb) including 5 m (16 ft) cable.
• Materials:
  • Sensor housing: UP (unsaturated polyester resin)
  • Cable gland: CuZn nickel-plated
  • Pipe adapter: CuZn nickel-plated
  • O-ring: VMQ
  • Seal: VMQ
  • Screws: V2A
  • Nameplate: 304 (1.4301)
  • Sensor membrane: FDU95-1**: 316L (1.4404) with PE coating; FDU95-2**: 316L (1.4404).
• Materials of connecting cable: VMQ.

Certificates and approvals

• CE mark
• RoHS (Restriction on Hazardous Substances Directive 2011/65/EU)
• RCM-Tick marking
• Ex approval: Available via Product Configurator.

Ordering information

Detailed ordering information is available via the Endress+Hauser website or Product Configurator.

• 5-point linearity protocol: Applies to the entire measuring system (sensor and transmitter). Span (S) is defined by Empty calibration (E) and Full calibration (F) values specified during ordering.
  • E ≤ 20,000 mm (787 in)
  • F = 450 to 18,000 mm (17.7 to 709 in)
  • A ≥ 2,000 mm (78.7 in) (A = distance from sensor membrane to 100%-point)

Scope of delivery

• Ordered version of the sensor.
• For certified versions: Safety Instructions (XAs).
• For sensors with Ex-certificate: process seal (VMQ).

Accessories

• Sensor extension cable:
  • Maximum permissible total length: 300 m (984 ft).
  • Cable type LiYY 2x(0.75)D+1x0.75 (PVC, –40 to +105 °C): Order number 71027743.
  • Cable type Li2G2G 2x(0.75)D+1x0.75 (Silicone, –40 to +150 °C): Order number 71027745.
• Screw-in flange FAX50: Mounting on rear thread G1 or NPT1. Available sizes in Product Configurator. Minimum nominal diameter: DN80 / NPS 3".
• FAU40 alignment unit: Used to align sensor with bulk solids surface. Swivel range: 15°.
• IP66 protective housing for RNB130 power supply unit: Order number 51002468.

---

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