Tecfluid Converter XL1, Инструкция по эксплуатации

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The textbox Cut off is useful to program the value below which the XL1 converter will
consider that the flow rate is zero, and therefore the analog output will give 4 mA and the
digital output will be deactivate if it is programmed as Pulses.
By default, the flowmeter is delivered programmed with a cut off value corresponding to a
liquid velocity of 0,5 m/s.
In the box Damping the value in seconds of the filter can be programmed. This filter allows to
obtain stable current readings despite of fluctuations of the flow rate.
The integration time is selected in seconds, with a minimum value of 1 and a maximum value
of 25 seconds.
When there is a sudden variation of the frequency then the filter should react as fast as possible
to give a correct reading of the new value. Therefore, the filter controls for each reading the
deviation of the instantaneous frequency with respect to a reference. If this deviation
exceeds 25%, the filter will stop acting, indicating the instant value, and will start again the
filtering process.
7.5.2 Units
In order to program the device more intuitively, the Flow rate units can be changed so that
the desired working units are selected. Programming parameters that have flow rate units
will update their value when the units are changed.
In the same way, the volume units related to the pulse output can be selected, which are given
in Pulses / Unit of volume.
7.5.3 Digital output
In the textbox Digital output this output can be configured as pulse output or as several
types of alarm.
As in the analog output, if the Bidirectional checkbox is selected, the pulse output will be
operative whether the flow rate is positive or negative.
If it is not selected, the pulse output will be operative only when the flow rate is positive.
In the textbox Number of pulses per volume unit, a number of pulses can be programmed.
This number will give information of each generated pulse, since this will correspond to a
determined volume. If the programmed value involves exceeding the maximum frequency
that the device can supply (5000 Hz), a warning message will appear.
In the textbox Duty cycle, the width of the output pulse can be programmed as a
percentage. The value indicates the percentage of time that the pulse is active with respect
to a complete period. The minimum and maximum values of Duty cycle are 10 and 90%.
Note: Regardless of the Duty cycle value, the pulse width can not exceed 180 ms.
When the digital output does not operate as a pulse output, it can be programmed as an
empty pipe indication, as an inverted flow indication or as a flow alarm.
In this latter case, the values corresponding to the activation and deactivation of the alarm
can be programmed.
7.5.4 Current loop calibration
The XL1 converter is delivered with the current output already calibrated. If you want to
correct a derive of the 4 or 20 mA current values because they do not coincide with the
ammeter used, it can be done in the following way:
To calibrate the 4 mA point, press the button “4 mA”. The transmitter will fix the output to
this value. Then enter the current value indicated in the multimeter and press the button
“Prog. 4 mA”. The transmitter will adjust its output and the multimeter will show 4 mA.