Offset - Tecfluid FLOMID Series Instruction Manual

The configuration of this filter can be very useful in the cases where the flow rate readings
have some instability (due to air bubbles, solids in suspension, etc.
Only the flow rate indication of the display is affected by the filter. The digital outputs and the
totalizer act according to the non-filtered flow rate. Selecting a filter with a longer or shorter
integration time will provide more or less stable readings and will also affect the response time
to small variations of flow rate.
The number of samples can be selected with a minimum value of 2 samples and a maximum
value of 250 samples. For example, with 15 samples, the display will indicate the flow rate
reading of the average flow rate over the last 15 flow rate samples measured.
For liquid velocities below 1 m/s, the filter is always operational. For velocities from 1 m/s,
when there is a sudden variation of flow rate, the filter should react as fast as possible to give
a correct reading of the new value. For this reason, the filter controls the deviation of the
instantaneous flow rate with respect to a reference for each reading. If this deviation exceeds
0.2 m/s, the filter stops acting, indicating the instantaneous value, and starting the filtering
process again.
7.4.4

Offset

In order to obtain a perfect linearization of the instrument, it is recommended to make an
adjustment of the zero offset each time an installation is performed, and if it is possible to
stop the flow rate.
The flow rate must be zero, that is, the liquid inside the pipe where the flowmeter is installed
should be completely stopped. Furthermore, a completely full pipe is necessary in order to
make an effective adjustment.
When the option Offset is selected, the following screen is shown:
When the flow rate is stable, press the key (Enter) and the instrument will save the value.
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