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DIAGNOSTIC MENU
The diagnostic menu shows a lot of parameters
that are mainly readable for experienced
users. The diagnostic data are also suited for
troubleshooting.
CAUTION
Diagnostic Window 1:
MENU 1: Diagnostic Data
Frequency:
Shows the signal frequency which depends
on the selected transducer.
There are three different transducers using different
frequencies (500kHz, 1000kHz, 2000kHz).
Signal:
Shows the type of signal code. Coded signals
allow reliable detection of signals.
T1:
Signal run time signal 1 (Upstream signal or down-
stream signal depending on connection of cables).
T2:
Signal run time of back signal 2 (Upstream signal or
downstream signal depending on connection of cables).
dT:
Measured difference between T1 and T2 (minus
zero offset if applicable). dT is proportional to flow.
vF:
Measured velocity
vS:
Measured speed of sound of fluid. Depends on
temperature.
SigQ:
Number of valid signals (in percentage). QStar
UFM makes numerous measurements per second and
automatically filters out unreliable signals. The number of
measurements in relation to valid measurements is SigQ.
The achievable number is related to the chosen quality
(see Menu 2). The higher the quality the lower usually
the SigQ. When setting quality to 0 there is basically no
filtering of signals and all signals are used for measure
-
ment (with the risk of using bad signals.
K-Factor:
Factor which compensates the influence
when measuring laminar flow (Re <8000). When
measuring in that area a (small) additional uncertainty
might occur.
Reynolds:
The number of Reynolds automatically
affects the chosen compensation factor.
Send Code (=signal sequence):
The used signal
sequence.
Diagnostic Menu 2:
MENU 2: Diagnostic Data
Theta:
Angle between ultrasonic path and flow vector.
Path length
: Length of acoustic path. Depends on pipe
size and on chosen installation mode of transducers.
(Delay):
Represents the time when the measuring
window starts.
Sensor distance:
Distance between the two trans-
ducers.
Bar index
: Mounting positions when using spacer bar.
Gain
: The required amplification (gain) of the signals
is automatically set continuously. 0 represents no
amplification (not applicable) while 255 represents the
maximum amplification. The lower the gain the better
the signal transmission. Very high gain might indicate
a disturbed signal (gas, particles, wrong mounting).
dT Corr:
Time shift of signals created by zero setting.
Quality:
The quality parameter represents the “thor
-
oughness” of the internal filter. Filter means that QStar
UFM checks each signal if plausible or not using the
quality parameter. When choosing quality 0, there will
be no filtering. That means that each signal is used for
measurement even the bad (and maybe wrong) ones.
Filtering of 100 would mean that filtering is very strict.
Both values ( 0/100) are not recommended. Typical
values are 50-75. When not getting measurement it
might be useful to set quality lower (for example, set
to 20).
Diagnostic Menu 3: