DAB PUMPS PWM 201, Инструкция по установке и обслуживанию

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On selection of one of the pre-defined sensors available, the diameter of the pipeline must be entered in inches in the page FD to
ensure correct flow readings (see section 6.5.10).
On selection of a pre-defined sensor, the setting of KF is disabled automatically. The parameter disabled message is displayed by
means of an icon with a padlock.
6.5.9.3 Operation with general flow sensor
This applies both to single and multiple sensors.
Use of the flow sensor enables effective measurement of the flow and the possibility of operation in special applications.
This setting enables use of a general pulse type flow sensor by setting the relative K-factor, i.e. the factor of pulse/litre conversion,
depending on the sensor and pipeline on which it is installed. This operating mode can also be useful in the case of using a pre-
defined sensor fitted on a pipe with a diameter not present in those available on the FD page. The k-factor can also be used when
fitting a pre-defined sensor, when the user requires a precise calibration of the flow sensor; obviously a precise flow measurement
device must be available. The setting of k-factor is made in the page FK (see section 6.5.11).
On selection of a general sensor, the setting of FD is disabled automatically. The parameter disabled message is displayed by
means of an icon with a padlock.
6.5.10 FD: Pipeline diameter setting
Diameter in inches of the pipeline on which the flow sensor is installed. This can only be set if a pre-defined flow sensor has been
selected. If FI has been set for manual entry of the flow sensor, or if operation without flow sensor has been selected, the parameter
FD is disabled. The parameter disabled message is displayed by means of an icon with a padlock.
The setting range is between ½ '' and 24''. The pipelines and flanges on which the flow sensor is fitted can be, according to diameter,
of different types and in different materials; the transit sections may therefore differ slightly. As calculations of the flow take into
account average conversion values to enable operation with all types of pipeline, this may cause a marginal error in reading the flow
rate. The value read may differ by a small percentage, but if the user requires a more precise reading, the following procedure is
possible: insert a test flow reading device on the pipeline, set FI for manual setting, modify the k-factor until the inverter shows the
same reading as the test instrument; see section 6.5.11. The same considerations apply when using a pipeline with non-standard
section; therefore: either enter the section closest to the effective value and accept the error margin, or change the setting of k-
factor, if required with reference to Table 20.
Incorrect settings of FD causes false flow reading with possible risk of shutdown
.
An incorrect selection of the diameter of pipeline where the flow sensor is to be connected may lead to flow reading errors
and system malfunctions.
Example: if a flow sensor is connected to a section of DN 100 pipeline, the minimum flow that the F3.00 sensor can read is 70.7
l/min. Below this flow rate, the inverter shuts down the pumps even in the case of a high flow rate, for example of 50l/min.
6.5.11 FK: Pulse/litre conversion factor settings
This expresses the number of pulses related to transit of one litre of fluid; it is based on the sensor used and section of the pipeline
on which it is installed.
If a flow sensor is fitted with a pulse type output, FK must be set according to the instructions of the sensor manufacturer.
If FI has been set for a specific sensor from the pre-defined series, or operation without flow sensor has been selected, the
parameter is disabled. The parameter disabled message is displayed by means of an icon with a padlock.
The setting range is between 0.01 and 320.00 pulses/litre. The parameter is applied by pressing SET or MODE. The flow values
found, but setting the pipeline diameter FD may differ slightly from the effective flow measured due to the average conversion factor
used in calculations, as explained in section
6.5.10
, and KF may also be used with one of the pre-defined sensors, both to operate
with non-standard pipeline diameters or to perform a calibration procedure.
Table 20 specifies the k-factor used by the inverter according to the pipeline diameter when using sensor F3.00.