Flexim FLUXUS F704**-A2 Series, User Manual

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11 Advanced Measuring Functions FLUXUS F70x
UMFLUXUS_F7V4-6-2EN, 2017-10-01 103
The measurement in the NoiseTrek mode can lead to a greater measurement error than in the TransitTime mode. There-
fore, even if there are valid measured values in the NoiseTrek mode, the transmitter can periodically toggle to the Transit-
Time mode in order to check if a measurement in the TransitTime mode is possible again. The time interval and the dura-
tion of the checking are set as follows:
In order to toggle between the TransitTime mode and the NoiseTrek mode manually during the measurement, press key
.
11.4 Upper Limit of the Flow Velocity
Single outliers caused by heavily disturbed surroundings can appear among the measured values of the flow velocity. If
the outliers are not ignored, they will affect all derived physical quantities, which will then be unsuitable for the integration
(e.g., pulse outputs).
It is possible to ignore all measured flow velocities higher than a upper limit. These measured values will be marked as
outliers.
The upper limit of the flow velocity is set in
Special Funct.\SYSTEM settings\Measuring\Velocity limit
.
If the flow velocity is higher than the upper limit,
• the flow velocity will be marked as invalid. The physical quantity cannot be determined.
• the LED of the measuring channel will light red (FLUXUS F709)
• "!" will be displayed after the unit of measurement (in case of a normal error, "?" is displayed)
If the automatic toggling between the TransitTime and the NoiseTrek mode is activated, the
toggling parameters have to be configured.
Enter the time after which the transmitter has to toggle to the NoiseTrek mode if there are
no valid measured values in the TransitTime mode. If 0 (zero) is entered, the transmitter
does not toggle to the NoiseTrek mode.
Enter the time after which the transmitter has to toggle to the TransitTime mode if there are
no valid measured values in the NoiseTrek mode. If 0 (zero) is entered, the transmitter
does not toggle to the TransitTime mode.
Enter the time after which the transmitter has to toggle to the TransitTime mode. If 0 (zero)
is entered, the transmitter does not toggle to the TransitTime mode.
Enter the time after which the transmitter has to toggle to the NoiseTrek mode if there are
no valid measured values in the TransitTime mode.
Example:
TT-Failed

NoiseTrek: After 40s
NT-Failed

TransTime: After 60s
NT-Ok,but check TT
:
Each
300s
Keep TT checking
:
For
5s
If no measurement is possible in the TransitTime mode for the duration of 40 s, the transmitter tog-
gles to the NoiseTrek mode. If no measurement is possible in the NoiseTrek mode for the duration of
60 s, the transmitter toggles back to the TransitTime mode.
If there are valid measured values during the measurement in the NoiseTrek mode, the transmitter
toggles to the TransitTime mode every 300 s. If no measurement is possible in the TransitTime mode
for the duration of 5 s, the transmitter toggles back to the NoiseTrek mode. If a valid measured value
is obtained in the TransitTime mode within the 5 s, the transmitter continues the measurement in the
TransitTime mode.
Enter 0 (zero) to switch off the checking for outliers.
Enter a limit > 0 to switch on the checking for outliers. The measured flow velocity will then
be compared to the entered upper limit.
Press ENTER.
Note! If the upper limit is too low, a measurement might be impossible because most of the measured val-
ues will be marked as "invalid".
TT-Failed |After

NoiseTrek | 40s
NT-Failed |After

TransTime | 60s
NT-Ok,but | Each
check TT | 300s
Keep TT | For
checking | 5s
Velocity limit
0.0 m/s