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FLOWSIC600 · Technical Information · 8010125 V 4.0 · © SICK AG
Flow Calibration
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3.3.8.3
Adjustment of the "Zero Phase" parameter
The zero phase should only be changed when the meter is at operating conditions.
Open the "Path Diagnosis" page (
).
Check the ultrasonic signals of both transducers for compliance with the following
criteria:
– Symmetric signal shape with a signal-to-noise ratio (SNR) >20 dB
– No signal deformation or bias in the region where the amplitude converges to zero
– Adaptation mean square error (MSE) < 0.008.
Properly adjusted zero phases of the individual paths are the basis for accurate measure-
ment of the ultrasonic signals‘ transit time.
The "Zero Phase" parameter of a path is properly adjusted, when the green cursor in the
signal window is symmetrically within the two dotted red limit lines and the red asterisk is
positioned exactly on the second positive zero crossing of the received ultrasonic signal
(
Figure 32
"Path Diagnosis" page in MEPAFLOW600 CBM
Diagnosis paths Green zero phase cursor Zero phase parameter