FAQ

The clamp-on sensors are fitted to the outside of the pipe – this means there is no need to cut into the pipe. They are secured using metal chains, metal straps or mounting rails. Coupling compound is applied to the underside of the sensor head to ensure acoustic coupling between the sensor and the pipe.

Advantages of installation:

• No process interruption
• No need to cut into the pipework
• No risk of leaks
• Installation can be completed in a matter of minutes

In most cases, no preparation of the pipe surface is necessary. Only very rough or corroded areas should be sanded smooth beforehand.

Katronic devices feature an acoustic sensor positioning assistant and an integrated setup wizard that guides you step by step through the installation process. This makes it possible to set up the measurement system and obtain accurate readings within a few minutes.

Yes. In addition to an integrated media library of standardised liquids and gases, you can enter custom substance data. To do this, select ‘User’ from the media selection menu. The flow meter will then prompt you to enter the following three parameters:

• Kinematic viscosity (mm²/s)
• Density (kg/m³)
• Sound velocity in the medium (m/s)

Often, the speed of sound in a medium (the speed at which sound travels through a fluid) is not known. In this case, you will find a list of parameters for non-standard media in the appendix to the operating instructions. If no suitable values are available there, please contact our technical support team.

Please note that manually entered parameters are only valid for the specified temperature.

For initial estimates, a water-like medium may also be used. To do this, select the medium ‘Water’ from the menu. Although this setting is not exact, water has average material properties that are required for the flow meter’s three measurement parameters. Although selecting ‘Water’ instead of another medium is not ideal, it does allow for initial indicative measurements. Please note that river water, wastewater, deionised water or sewage sludge are also classified as ‘Water’ and differ only in their solids content.

For precise measurements, however, project-specific material data is recommended.

No, as long as the paint layer is firmly adhered and uniform. Only if the paint is flaking or there are several different layers should the surface be prepared locally using a suitable abrasive.

The achievable accuracy depends on the application of the flow meter:

• Volume flow without process calibration: ±1% to ±3%
• With on-site process calibration: ±0.5 %
• Flow velocity: ±0.5 %
• Measurable flow velocity range: 0.01 to 25 m/s; reproducibility: 0.15 % of the measured value.

Katronic’s clamp-on sensors cover a very wide range of pipe diameters, from 10 mm to 6,500 mm.

No. The measuring instruments operate without wear and tear because:

• there are no moving parts,
• no components that come into contact with the medium are used, and
• the sensors are mounted on the outside of the pipe wall and are made of stainless steel (Note: This applies to all types except the P-sensors).

Corrosion, pressure loads or the effects of the process medium do not affect the sensor technology. Maintenance is therefore not necessary.

When fully charged, the KATflow 200 and KATflow 230 portable measuring devices can operate continuously for up to 24 hours. The full charging time is approximately twelve hours.

Activated analogue outputs or additional functions on the KATflow 230 increase energy consumption, thereby reducing battery life. Deactivate the outputs in the menu when not in use.

For long-term measurements, the KATflow 210 is available with a battery life of up to 100 days. The measuring instrument offers various battery configurations and can be operated in three different measurement modes to enable the longest possible measurement periods.

Should a KATflow flow meter fail to achieve the expected battery life, please contact Katronic or our sales partners. All Katronic flow meters can also be operated from the mains, thus ensuring continuous operation, albeit only temporarily.

Standard cable lengths range from 2.5 m to 30 m, depending on the sensor type. Extension cables of up to 200 m are available as an option. You can find a detailed overview of these in our product brochure.

First, ensure that the flow meter is fully charged. Connect the device to the charger. The flow meter should now switch on and the battery indicator should flash to show that it is charging. If this is not the case, please contact Katronic.

If the flow meter is running on mains power, switch it off, disconnect it from the mains supply and try to restart it by holding down the <ENTER> button.

If the device still won’t switch on, open the battery compartment, remove the batteries and check their condition. Then reinsert the batteries and repeat the

start-up procedure. If the screen remains blank, the batteries may need replacing. Please contact the manufacturer for further information.

All permanently installed flow meters switch on automatically as soon as power is supplied. If this does not happen, please carry out the following checks:

1. Check the power supply:

Use a multimeter to ensure that current is flowing at the flow meter’s main connection.

2. Check the fuses:

Check the flow meter’s fuses and replace them if necessary.

3. Check the wiring:

Use the wiring diagram provided in the operating instructions to ensure that the wiring is correct.

4. Check the supply voltage:

Ensure that the flow meter is supplied with the correct voltage. If a suitably marked AC/DC multimeter indicates an incorrect supply voltage, disconnect the device from the mains immediately and contact our technical support, as the electronics may have been damaged.

This code is an error message and usually means:

• The Pt 100 temperature sensor is not correctly connected to the flow meter,
• defective Pt 100 temperature sensor,
• a break in the cable, or
• incorrect wiring.

Please refer to the user manual for information on correct wiring. Once the

connection, the temperature measurement will function correctly again.

In most cases, the cause lies not with the measuring instrument but with the process conditions.

First, check the following points:

1. Is there actually any flow?
2. Is the pipe completely full?
3. Are the sensor spacing and alignment correct?
4. Are the signal and noise values within the permissible limits?

To do this, press <DISP> on the flow meter’s keypad to access the diagnostics menu, then press <NEXT> until the following values are displayed:

• Gain
• Signal
• Noise

The flow meter has these three preset limit values; under normal conditions, no measurement is possible outside these limits:

• If the signal falls below -10 dB, no valid measurement is possible.
• If the noise rises above 10 dB, a valid measurement is not possible.
• If the SNR is < 6 dB, a valid measurement is not possible.

SNR (Signal-to-Noise Ratio) is the difference between the signal and the noise; for example, a signal of 15 dB and noise of -15 dB result in an SNR of 30 dB.

If a strong signal is displayed but no flow rate is shown, the noise is often too high. In this case, check the sensor cabling for loose wires and consider earthing the cable shields.

Alternatively, you can make a note of the diagnostic values mentioned above and contact technical support if the problem persists.

For a reliable measurement, a signal level of at least -10 dB and an SNR of at least 6 dB must be achieved. If these values are not met, this may be due to the following causes:

Air pockets or a partially filled pipe

• If the pipe is empty or only partially filled, the flow meter cannot detect a sufficiently strong signal.

Heavily corroded or damaged pipe surface

• Rust, flaking paint or a rough surface can impair signal transmission. Clean the measurement point and, if necessary, smooth the surface using a file, wire brush, sandpaper or a sander.

Inappropriate mounting position

• For horizontally running pipes, the sensors should be mounted on the side, not at the top or bottom. Further guidance can be found in the manual, the quick start guide or the installation videos.

Incorrect sensor alignment

• Install the sensors at the distance recommended by the Acoustic Sensor Positioning Assistant. The arrows engraved on the sensors must point in the direction of flow.

Insufficient coupling between sensor and pipe

• Apply a sufficient amount of coupling gel to the sensor surfaces. Air between the sensor and the pipe significantly weakens the signal.

High gas or solid content in the medium

• A high proportion of gases or solids can affect the measurement. Ensure that the medium is suitable for the measurement.

Incorrect sensor cabling (for permanently installed devices)

• Check the wiring in accordance with the instructions in the manual.

Tip:

If the signal remains weak, reduce the number of sound paths to a maximum of one to maximise the available signal. If the problem persists, please contact technical support.

If the flow meter has been operating continuously and the measurement suddenly stops, you should check the following points:

1. Check the process conditions

• Is the liquid still flowing?
• Is the pipe completely full?

2. Check the sensor installation

• Check whether the sensors are still securely mounted on the pipe.
• Is there a connection between the sensors?
• Check the sensor connections and cables.

3. Check the settings in the menu

In the menu, open the item <System – Calibration – Zero – Zero Tracking> and ensure that Zero Tracking is set to <OFF>.

Also check the damping under <Output – Display – Damping>. For varying flow conditions, a damping time of approx. 5 s is recommended.

4. Take temperature changes into account

Significant temperature fluctuations in the process can affect the measurement. If your process is subject to major temperature changes, it may be advisable to use a Pt 100 temperature sensor to compensate for temperature drifts.

Generally speaking, no. The measurement is based on the transit time difference method and does not require any pipe-specific factory calibration. Once the application parameters (pipe diameter, pipe material, wall thickness, medium, etc.) have been entered, the accuracy specified above is achieved. An optional on-site process calibration can be carried out if particularly high accuracy requirements apply.

A calibration certificate confirms that the measurement system in use, comprising an ultrasonic flowmeter and a pair of clamp-on sensors, delivers readings within the specified accuracy range at various flow velocities. It is primarily used for quality assurance or compliance documentation, but is not strictly necessary for normal operation. Calibration can be carried out at the customer’s request for a fee.

No. Once correctly installed, the coupling remains stable in the long term. A visual inspection of the sensor wetting is only recommended under extreme environmental conditions, typically as part of an annual system inspection.

Enquiries regarding gas flow measurement are generally more complex than those involving liquid media and require a more detailed preliminary assessment. The main differences are:

Different types of waves

• Liquids: shear waves
• Gases: Lamb waves

Greater attenuation in gases

• Gases attenuate the signal significantly more. Consequently, a higher energy input is required to obtain a usable signal.

Limited measurability

• Whilst almost all media can be measured in liquids, this is only possible to a limited extent with gases.

Dependence on process parameters

• The measurability of gases depends heavily on factors such as density, temperature, pressure and composition.

Important:

For gas applications, it is therefore always necessary to carry out a feasibility check based on the application parameters beforehand – usually before a quotation is provided.

Several application parameters are required to evaluate gas applications. These are crucial for selecting a suitable measuring instrument.

Please provide the following information:

• Pipe material
• Pipe diameter
• Pipe wall thickness
• Medium / gas composition
• Operating pressure
• Temperature
• Flow velocity

Note: 

The more complete this information is, the quicker and more accurately we can assess feasibility and select a suitable unit.