Prosonic FMU30

Summary

Product identification

• Product Name: Prosonic T FMU30
• Type: Ultrasonic Level Measurement
• Description: Compact transmitters for non-contact level measurement of fluids, pastes, and coarse bulk materials.

Application

• Continuous, non-contact level measurement in fluids, pastes, sullages, and coarse bulk materials.
• System integration via 4 to 20mA output.

Measuring Range

• 1½" sensor:
  • 5 m (16 ft) in fluids
  • 2 m (6.6 ft) in bulk materials
• 2" sensor:
  • 8 m (26 ft) in fluids
  • 3.5 m (11 ft) in bulk materials

Features and Benefits

• Quick and simple commissioning via menu-guided on-site operation with a four-line plain text display.
• Seven languages selectable.
• Envelope curves on the on-site display for simple diagnosis.
• Linearization function (up to 32 points) for conversion of measured values.
• Non-contact measurement method minimizes service requirements.
• Installation possible from G 1½“ or NPT 1½“ threads upwards.
• Integrated temperature sensor for automatic correction of temperature-dependent sound velocity.

Measuring Principle

The instrument uses the time-of-flight method. It transmits ultrasonic pulses, which are reflected by the product surface. The time taken for the pulse to return is measured to calculate the distance to the product surface. Level is then calculated using the known empty distance. An integrated temperature sensor compensates for changes in the velocity of sound.

Interference echo suppression is available to prevent false readings from obstacles. Calibration requires input of the empty distance and span. The span must not extend into the blocking distance.

Equipment Architecture

The measuring system comprises the Prosonic FMU30 transmitter, and can be operated on-site with its display module or remotely using a PC with software like FieldCare and a Commubox FXA291 with a ToF Adapter FXA291.

Input

Measured Variable

The primary measured variable is the distance (D) between the sensor membrane and the product surface. This can be used to calculate:

• Level (L) in any units.
• Volume (V) in any units.
• Flow (Q) in open channels or measuring weirs.

Measuring Range Limitations

The measuring range is influenced by various factors, including:

• Fluid surface: Calm (0 dB), Waves (5 to 10 dB), Strong turbulence (10 to 20 dB), Foaming (contact sales).
• Bulk material surface: Hard, rough (40 dB), Soft (40 to 60 dB).
• Dust: No dust formation (0 dB), Little dust formation (5 dB), Heavy dust formation (5 to 20 dB).
• Filling curtain: None (0 dB), Small quantities (5 to 10 dB), Large quantities (10 to 40 dB).
• Temperature difference: to 20 °C (0 dB), to 40 °C (5 to 10 dB), to 60 °C (10 to 15 dB).

An example calculation for a 2" sensor in a dusty environment with a filling curtain and temperature difference indicates a range of approximately 3.5 m.

Operating Frequency

• 1½" sensor: approx. 70 kHz
• 2" sensor: approx. 50 kHz

Output

Output Signal

• 4 to 20 mA

Signal on Alarm

Error information can be accessed via the on-site display or the current output. The signal on error can be selected, for example, according to NAMUR recommendation NE43.

Output Damping

Freely selectable: 0 to 255 s.

Linearization

Allows conversion of the measured value into any unit of length or volume. Flow linearization is possible for open channels or measuring weirs. A preprogrammed linearization table for horizontal cylindrical tanks is available. Custom tables with up to 32 value pairs can be entered.

Power Supply

• Supply voltage: 14 to 35 V DC
• Power consumption: 51 mW to 800 mW
• Current consumption: 3.6 to 22 mA

Terminal Compartment

Terminals are located underneath the housing cover.

Performance Characteristics

• Reaction time: Minimum 2 s (parameter dependent).
• Reference operating conditions: Temperature +20 °C, Pressure 1013 mbar abs., Humidity 50%, ideal reflective surface, no interference.
• Measured value resolution: 1 mm (0.04 in).
• Pulse frequency: max. 0.5 Hz.
• Maximum measuring error: ±0.2 % of the maximum span of the sensor (according to EN 61298-2).
• Typical measuring error: Better than ±3 mm or 0.2 % of measuring distance, whichever is greater.
• Influence of vapor pressure: High accuracy is possible if vapor pressure at 20°C is below 50 mbar. High vapor pressures or outgassing media can influence accuracy.

Installation

Installation Variants

• Installation with counter nut.
• Installation with sleeve.
• Installation with installation bracket.
• Installation with screw-in flange.

Installation Conditions for Level Measurements

• Avoid installing the sensor in the middle of the tank.
• Protect the device from direct sun or rain.
• Avoid measurements through the filling curtain.
• Align sensor membrane perpendicular to the surface for bulk solids with cones.
• Ensure other equipment is not within the emitting angle.
• Do not install two ultrasonic devices in the same tank.
• The 3 dB emitting angle is used to estimate the detection range.

Installation in Narrow Shafts

For narrow shafts with strong interference echoes, an ultrasound guide pipe (minimum diameter 100 mm) is recommended.

Installation Conditions for Flow Measurements

• Install at the inflow side, close above the maximum water level (consider blocking distance).
• Position in the middle of the channel or weir.
• Align sensor membrane parallel to the water surface.
• Adhere to installation distances for the channel or weir.

Blocking Distance, Nozzle Installation

The instrument must be installed so the blocking distance is not undershot. A pipe nozzle may be used if necessary. The nozzle interior should be smooth. An angled socket edge (ideally 45°) is recommended.

• Nozzle diameter: Ranges from DN50/2" up to DN300/12".
• Maximum nozzle length: Up to 400 mm (15.7 in) depending on nozzle diameter and sensor size.
• Blocking distance (BD): 0.25 m (0.8 ft) for 1½" sensor, 0.35 m (1.1 ft) for 2" sensor.

A safety distance (SD) can be specified to warn if the level approaches the blocking distance.

Environment

• Ambient temperature range: -20 °C to +60 °C (-4 °F to +140 °F).
• Storage temperature: -40 °C to +80 °C (-40 °F to +176 °F).
• Resistance to alternating temperature cycles: Tested according to DIN EN 60068-2-14.
• Climate class: DIN EN 60068-2-38.
• Ingress protection: IP68 (24h at 1.83 m underwater) with closed housing, IP66 with closed housing, IP20 with open housing.
• Vibration resistance: Tested according to DIN EN 60068-2-64.
• Electromagnetic compatibility (EMC): Meets requirements for "industrial environment" according to EN 61326. Influence of EMC < 1 % FS.

Process

• Process temperature range: -20°C to +60°C (-4 °F to +140 °F).
• Process pressure range: 0.7 bar to 3 bar abs. (10.15 psi to 43.5 psi).

Mechanical Construction

Design; Dimensions

Dimensions vary slightly between the 1½" and 2" sensor versions.

Weight

• 1½" sensor: approx. 0.75 kg (1.65 lbs).
• 2" sensor: approx. 0.8 kg (1.76 lbs).

Housing Design

• Housing type: F16 plastic housing.
• Cover: Plastic cover (low for non-display, high for display versions).

Process Connection

• 1½" sensor: Thread G 1½“, PP or Thread MNPT 1½“ - 11.5.
• 2" sensor: Thread G 2", PP or Thread MNPT 2" - 11.5.

Materials

Chemical compatibility must be checked for the following materials:

• Cover: PBT or PA.
• O-ring: EPDM.
• Sensor: PP.
• Matching Layer: EPDM.
• Counter nut: PC.
• Sealing: EPDM.
• Housing Adapter: PBT GF 30-FR.
• Goretex filter: PBT-20GF.
• Cable gland: Polyamid (PA).
• Plug: PBT-GF30.
• Housing: PBT-FR.

Operability

Display and Operating Elements

The LCD module is located beneath the housing cover. It includes a display symbol, display screen, plug-in module, and function keys.

On-site Operation

Configuration can be done directly at the instrument using 3 keys and a menu system. Seven languages are available.

Remote Operation

Operation with FieldCare (Endress+Hauser's FDT based Plant Asset Management Tool) is possible using a Commubox FXA291 and ToF Adapter FXA291. FieldCare supports various communication protocols and offers functions like signal analysis, linearization table editing, and data upload/download.

Certificates and Approvals

• CE mark: Confirms compliance with EC directives.
• Ex approvals: ATEX, IECEx, CSA C/US, NEPSI. Additional safety instructions are required for hazardous areas.

Ordering Information

The order code is built by selecting options for various features:

• Approval: Non-hazardous, ATEX, CSA C/US, IECEx, NEPSI, Special version.
• Display; Operating: Without display, Envelope curve display on site, Special version.
• Electrical Connection: Gland M20, Thread G1/2, Thread NPT1/2.
• Sensor; Max Range; Blocking Distance: 1½" (5m/2m, 0.25m BD), 2" (8m/3.5m, 0.35m BD), Special version.
• Process Connection: ISO228 G1-1/2, ISO228 G2, MNPT1-1/2, MNPT2, Special version.
• Accessory Enclosed: Various UNI flange options (2", 3", 4", 6", DN200, DN250) with different materials (PP, PVDF, 316L), Special version.
• Marking: Tagging.

Scope of Delivery

• Instrument as per ordered version.
• Short instructions.
• For certified versions: Safety Instructions, Control- or Installation drawings.
• Counter nut (PC) and Sealing ring (EPDM) for certain process connection options.
• Cable gland for 2-wire instruments.

Accessories

• Installation bracket: Available for G 1½" and G 2" process connections.
• Screw-in flange: Various flange types (steel, PP, PVDF, 316L) and sizes are available.
• Cantilever with mounting frame or wall bracket: For installation with cantilevers.
• Weather protection cover: Recommended for outdoor mounting.
• Commubox FXA291: Connects instruments to a PC via USB.
• ToF Adapter FXA291: Required for connecting the Commubox to the FMU30.

Documentation

• Operating manual (BA00387F): Covers installation and first commissioning.
• Description of device functions (BA00388F): Detailed description of all functions.
• Short instructions (KA01054F): For rapid commissioning.
• Safety Instructions (XA): Supplied for certified device versions.

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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)

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