Ultraflux Uf 841, User Manual

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NT UF 841 CP GB (d) / June 2015
3) Delta T0 and Auto zero
The DeltaT0 field is used to correct installation errors. For example, it is possible to compensate for a bias
due to an incorrect position of the probes by adding to DeltaT0 the value required in order to rectify it.
It is also possible to launch an automatic determination mode for the Delta T0 by selecting a time (30 s, 1
min, etc.) in "Autozero".
Warning: before doing this, ensure that the pipe is definitely at rest.
4) C0 and Delta C
With a "normal" configuration, it is possible to select a fluid and its associated celerity from a non-exhaustive
list. The celerity relating to the selected fluid is displayed automatically in the C0 field. If a fluid not shown in
the list, you can select "Product = OTHER" and define a special C0 value (the C0 field becomes editable).
The Delta C is used to indicate to the flow meter the variation in the speed of the sound and therefore the
"search" area for the ultrasound echo. To use this variable, it is preferable to use the standard settings and
launch the echo display (see the "Echo display menu" section).
If the echo is outside the search window, you can:
- change the C0 to re-centre the window,
- change the Delta C to widen or shorten the search window.
If the echo is on the right, the value of C must be lowered.
Conversely, if the echo is on the left, the value of C must be increased.