DUK - Small Inline Ultrasonic Flow Meter - High Turndown Ratio

• Accuracy for media viscosity <10 cSt (Water or Water-Glycol): ±0.7% of reading + ±0.7% of full scale
• Accuracy for media viscosity >10 cSt: ±1.5% of reading + ±0.7% of full scale
• Repeatability: ±0.1% of full scale

These specifications apply under reference conditions: media temperature 59-86°F, 14.5 PSI, with pipe connection internal diameter ≥ connection size and flow in direction of arrow on meter body.

• Maximum Operating Pressure: 230 PSI (16 bar)
• Media Temperature Range: -4°F to 194°F (-20°C to 90°C)
• Ambient Temperature Range: -4°F to 158°F (-20°C to 70°C)

The pressure loss for each flow range is 2.2 PSI (150 mbar) maximum at full scale flow.

The DUK is available with a variety of materials to fit a wide range of media and process conditions.

• Body: Brass or 316 SS
• Sensors: PEEK
• Seals: NBR, FKM, EPDM

The DUK is designed for:

• Water: Primary media (factory default configuration and calibration media)
• Water-glycol mixtures: Various concentrations (20%, 34%, 39%, 52%)
• Oils: ISO VG grades 10, 22, 32, 46, 68 (different configurations for different pipe sizes)
• Other liquids: Ethanol, diesel, gasoline, various acids, petroleum products
• Many other common media types (see DUK media tables available as a PDF in the MEDIATOR Tool software package)

The maximum media viscosity of 3 cSt is for the basic device configurations, but the DUK equipped with the U-PACE electronic have a 68 cSt maximum.

A comprehensive media database with 50+ pre-configured media types is available via the MEDIATOR Tool software (note the U-PACE C3T0 electronic option and KOFICOM-IFMU accessory is required to upload media configuration from the media database to the device).

Yes, the DUK with the optional U-PACE C3T0 electronic provides true bidirectional measurement with directional indication:

• Positive/Negative flow indication with ± symbols on display
• Configurable totalization: Absolute or bidirectional counting modes
• No flow restrictions - symmetric design works equally in both directions

Note that while the DUK offers bidirectional flow measurement capabilities the arrow marking on housing indicates the positive flow direction and the unit must be installed accordingly.

• Straight pipe runs: 10x pipe diameter upstream and downstream of meter
• Mounting orientation: Universal - can be installed vertically, horizontally, or at an angle
• Flow direction: Must follow the arrow marking on the device
• Recommended: Install inlet/outlet pipes at least 50mm from connections
• Avoid: Valves or large reductions on inlet section, pressure surges, extreme vibrations

The DUK offers multiple electronic configurations with either basic outputs or advanced electronics:

Basic Outputs (blind outputs):

• Switching outputs: Relay (S300) or active 24VDC (S30D) with configurable setpoints
• Analog outputs: 4-20mA (L343 or L443)
• Frequency outputs: 500 Hz standard (F300) or 50-1000 Hz user-configurable (F390)

Advanced Electronics (C3T0):

• TFT display (128×128 pixels, rotatable in 90° increments)
• 2× configurable outputs
  • Switching Output NPN/PNP/PP
  • Pulse Output PP
  • Frequency Output PP
  • 4-20 mA Analog Output
  • 0-10 VDC Analog Output
• IO-Link communication mode
• Dosing function with external control input

The C3T0 can be configured as follows:

Using the 4 optical touch keys around the TFT display (activated by blue backlighting) the user can navigate the intuitive menu system. To enter the system menu, hold the menu button for 3-5 seconds. In the system menu, the parameters are divided into main groups and subgroups. Use the up and down buttons to navigate the current screen, the forward button to advance into a subgroup, and the backwards button to return to the previous level. Once in the subgroup menu you can navigate to the specific parameters in the same fashion. Use the up and down buttons to set the parameters as desired and the forward button to save the setting.

Below are some of the settings that can be changed:

• Display layouts: Single or dual measurement display
• Outputs displayed: Flow, Total Volume, Part Volume, or Temperature readings (up to two at a time)
• Output types: Frequency, Switching, Relay Analog, or IO-Link mode
• Configurable parameters: Filter settings, output scaling, alarm thresholds
• User hotkeys: Two programmable function keys for quick access to MIN/MAX, reset functions
• System units: GPM, LPM, Gallons, Liters, °F, °C, etc.
• Screen Orientation: Rotate the screen direction to match your installation

See the U-PACE electronics operating manual for more information about settings and configuration.

The C3T0 electronics include IO-Link capability, providing advanced digital communication and connectivity benefits:

• The IO-Link Specifications for this device:
• IO-Link Specification: V1.1
• Manufacturer Name: Kobold Messring GmbH
• Bitrate: COM3
• Minimum cycle time: 1.1 ms
• SIO-Mode: Yes (OUT1 in Configuration IO-Link)
• Maximum cable length: 20 meters
• Block parameterization: Yes
• Operational readiness: 10 seconds
• Manufacturer ID: 1105 (Decimal), 0x0451 (Hex)

Process Data Inputs:

• Flow: 32 Bit, Float
• Volume: 32 Bit, Float
• Temperature: 12 Bit, Integer
• Status Out 1: 1 Bit, Boolean
• Status Out 2: 1 Bit, Boolean

Diagnostic Functions:

There are many diagnostic event codes to report device errors, refer to the specific device manual for the DUK for more information.

The DUK with the U-PACE C3T0 electronic is known for its ease of integration and use. The C3T0 will help to simplify operations in the following ways:

• Plug-and-Play Connectivity: Automatic device recognition and configuration when connected to IO-Link masters
• Standard 3-wire Connection: Uses existing M12 sensor cables - no special wiring required
• Multi-vendor Interoperability: Works with any IO-Link master from different manufacturers
• Scalable Architecture: Easily integrate single devices or build complex networks

The IO-Link feature of the C3T0 option of the DUK provides many great communication benefits such as:

• Bidirectional Data Exchange: Real-time process data transmission plus parameter configuration
• Multiple Data Points: Simultaneous access to flow rate, temperature, totalizer values, and status information
• Block Parameterization: Upload/download complete device configurations for rapid commissioning
• Device Identification: Automatic detection of device type, serial number, and firmware version
• Diagnostic Function: Error codes for device malfunction to aid in troubleshooting

Power requirements vary by electronics type:

• Basic electronics (S300/S30D/F3x0/L3x3): 24 VDC ±20%, from 25 mA up to 45 mA consumption depending on the specific electronic
• C3T0 Compact electronics: 19-30 VDC, maximum 200 mA consumption

The wiring configuration of the M12 connector depends on the electronic output type of the device.

For the DUK-…S30D with M12x1, 4-pin configuration:

• Pin 1: +Vs (24 VDC supply)
• Pin 2: Signal Output (N/C)
• Pin 3: GND (Ground)
• Pin 4: Signal Output (N/O)

For the DUK-…F3x0 and DUK-…L343 with M12x1, 4-pin configuration:

• Pin 1: +Vs (24 VDC supply)
• Pin 2: n.c. (Not Connected)
• Pin 3: GND (Ground)
• Pin 4: Signal Output (Frequency or Analog)

For the DUK-…C3T0 with M12x1, 4-pin configuration:

• Pin 1: +Vs (24 VDC supply)
• Pin 2: Signal Output (Configurable)
• Pin 3: GND (Ground)
• Pin 4: Signal Output (Configurable)

For the DUK-…S300 with M12x1, 5-pin configuration:

• Pin 1: +Vs (24 VDC supply)
• Pin 2: Signal Output (N/O)
• Pin 3: GND (Ground)
• Pin 4: Signal Output (N/C)
• Pin 5: Output Common

Refer to the datasheet and manual for more specific information about the electrical connections.

The DUK requires very minimal maintenance:

• No routine maintenance is required if the medium doesn't cause deposits
• If sensor is fouled, it can be rinsed with suitable liquid and fiber/particles can be gently removed with a cleaning cloth
• Electronics service: Any service on the unit's electronics will void any warranty. Electronics issues should be reported to Kobold for evaluation.

Common troubleshooting steps:

• Verify installation: Confirm proper straight pipe runs and flow direction
• Inspect for air bubbles or solids: Can significantly affect ultrasonic measurement
• Check electrical connections: Verify proper wiring and supply voltage
• Verify media: Certify that media viscosity is within meter limits
• Review filter settings: Adjust filtering for pulsating flows (use exponential smoothing)
• Validate flow range: Ensure operation within specified measuring range

The dosing function provides:

• Fixed output assignments: OUT2 (Pin 2) becomes dosing output (push-pull), OUT1 (Pin 4) becomes control input
• Control methods: START/STOP/RESET via softkeys or external control input

Control input timing:

• START/STOP: 0.5s < t_high < 4s
• RESET: t_high > 5s

Parameters: Dosing quantity, correction value, timeout monitoring

Visual feedback: Graphic animation showing container fill amount

The C3T0 offers three filter types to compensate for noisy signals:

• Standard filter: Rolling average with step detector and fastest response time
• IIR filter: Digital low-pass, 1st order infinite response for low to medium pulsating flows
• Exp. smoothing: Exponential smoothing filter best for strong pulsating flows

For pulsating pumps: Use exponential smoothing filter, ensure pulsation peaks stay within measuring range, avoid frequencies near 50 Hz or its divisors.

When equipped with the C3T0 electronic all analog outputs can be activated according to NAMUR NE43 where:

• Normal operation: 4-20 mA becomes 3.8-20.5 mA linear output
• Overflow condition: Current jumps to ~22 mA (measuring range overshoot)
• Underflow condition: 3.8-4.0 mA indicates measuring range undershot
• Fault condition: ~3.6 mA indicates device/process fault (e.g., empty tube)

To activate NAMUR behavior, navigate to menu to the sub-parameter level 2 of the desired output and choose NAMUR Standard to activate.

• Protection rating: IP65
• EMC compliance: EN 61326-1:2013
• RoHS compliance: 2011/65/EU, 2015/863/EU

• Connection cables: 4-pin (P/N 807.037) and 5-pin (P/N 807.007) M12 connectors with 6-foot cables
• KofiCom Interface Set: PC interface for configuration and diagnostics
• Media configurations: Pre-configured parameter sets for various liquids (ordering code ABG-DUK)
• MEDIATOR Tool: Free Windows software for media table management

Both inline and clamp-on ultrasonic flowmeters operate using sonic waves to determine the speed of the fluid based on the Transit Time Method. They diverge in how they are installed, their ease of configuration, and intended uses. The inline meters are mounted directly in the flow path and are in contact with the fluid, where clamp-on meters are mounted on the outside of the pipe and never contact the media.

Installation:

Inline meters are installed in the piping network through threaded fittings, flanges, or other types of connections. For new installations, this is usually straightforward, but for retrofits on existing systems this can be cumbersome as it requires a process shutdown and modifications to the existing piping network. As this meter is in direct contact with the process media, the selection of the meter's wetted parts must be chosen so that are compatible with the fluid.

Clamp-on meters are installed on to the outside of the pipe and can be mounted without interrupting the process. While initial installation is less intrusive, it requires precise positioning and setup of the transducers for accurate reading. The pipe material and quality also can affect the performance. Installation near any pipe seams must be avoided and any pipe coatings (insulation, paint, surface contamination) must be removed. An ultrasonic coupling gel must be applied between the transducer and pipe, which creates a recurring maintenance task.

Configuration, Startup, and Performance:

The DUK inline meters are factory calibrated and scaled and therefore require little set-up once installed in the process line.

On the other hand, clamp-on meters require precise installation according to manufacturer's instructions, input of various parameters such as pipe diameter, wall thickness, pipe material, and the process media properties, some of which may not be easily attainable. Once parameterized, a zero point calibration should be carried out and flow should be checked at multiple points to confirm correct setup.

Main benefits of inline over clamp-on ultrasonic flowmeters:

• Consistent Results: Performance independent of pipe material (steel, plastic, concrete, etc.) and direct measurement allows consistent signal path eliminating pipe material, thickness, and coating variables
• Predictable Performance: Factory calibrated with guaranteed specifications without the complicated configuration and start-up requirements of a clamp-on
• Lower Maintenance: No transducer repositioning or coupling compound maintenance

When to Choose Inline vs. Clamp-On:

• Choose Inline: New installations, permanent measurement points, high accuracy requirements, and smaller pipe diameters
• Choose Clamp-On: Temporary measurements, existing pipe retrofits, large diameter pipes

The DUK offers several unique advantages over competitive inline ultrasonic flowmeters:

• Large flow measurement range: 250:1 turndown ratio to measure extremely low flows while maintaining high-end capability
• Integrated Electronics: No separate transmitter housing required
• Easy Installation: Fits in tight spaces where larger competitors cannot
• Unique TFT Display: Configurable color display with rotatable screen to fit any installation orientation
• Dual Configurable Outputs: Simultaneous outputs configurable as analog, frequency, or switching
• IO-Link Integration: Advanced Industry 4.0 connectivity
• Integrated Dosing Function: Built-in batching capability eliminates need for external controllers
• Extensive Media Database: 50+ pre-configured media types with MEDIATOR Tool
• Higher Viscosity Range: Up to 68 cSt with C3T0 electronics
• Housing Material Options: Brass or 316 stainless steel

The DUK ultrasonic flowmeter is the perfect alternative to magnetic flowmeters when dealing with non-conductive or low-conductivity media:

• No conductivity requirement: measure any clean media regardless of conductivity where magnetic flow meters require minimum conductivity of 5-20 μS/cm
• Less media restrictions: Can measure pure water, oils, hydrocarbons, alcohols, or most organic solvents