Endress+Hauser Proline Prowirl 72, Operating Instructions Manual

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9 Trouble-shooting Proline Prowirl 72
50 E Hauser
9.3 Process errors without messages
Symptoms Remedial measures
Remark:
You may have to change or correct settings in certain functions of the function matrix in order to rectify faults. The
functions outlined below, such as FLOW DAMPING etc. are described in detail in the section "Description of device
functions" on Page 71 ff.
No flow signal • For liquids:
Check whether the piping is completely filled. The piping must always be
completely filled for accurate and reliable flow measurement.
• Check whether all the packaging material, including the meter body protective
covers, was completely removed before mounting the device.
• Check whether the desired electrical output signal was connected correctly.
Flow signal even though there is
no flow Check whether the device is exposed to particularly strong vibrations. If so, a flow
can be displayed even if the fluid is at a standstill, depending on the frequency and
direction of the vibration.
Remedial measures at the device:
• Turn the sensor 90 ° (note therefore the installation conditions, see
→
Page 12 ff.). The measuring system is most sensitive to vibrations which follow
in the sensor axis. Vibrations have less of an effect on the device in the other axes.
• The amplification can be altered using the AMPLIFICATION function
(
→
Page 101).
Remedy through constructive measures during installation:
• If the source of the vibration (e.g. pump or a valve) has been identified, the
vibrations can be reduced by decoupling or supporting the source.
• Support the piping near the device.
If these measures do not solve the problem, your Hauser service
organization can adjust the filters of the device to suit your special application.
Faulty or highly-fluctuating flow
signal • The fluid is not adequately single-phase or homogeneous. The piping must always
be completely filled and the fluid must be single-phase and homogeneous for
accurate and reliable flow measurement.
• In many instances, the following measures can be taken to improve the
measurement result even under non-ideal conditions:
– For liquids with a low gas content in horizontal pipework, it helps to install the
device with the head pointing downwards or to the side. This improves the
measuring signal since the sensor is not in the area where gas accumulates
when this type of installation is used.
– For liquids with a low solids content, avoid installing the device with the
electronics housing pointing downwards.
– For steam or gases with a low liquid content, avoid installing the device with
the electronics housing pointing downwards.
• The inlet and outlet runs must be present as per the installation instructions
(
→
Page 14).
• Suitable seals with an internal diameter not smaller than the pipe internal
diameter must be installed and correctly centered.
• The static pressure must be large enough to rule out cavitation in the area of the
sensor.
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