Aalborg PWE Digital - Manual (Page 50)

4.9.3 Submenu Flow Meter Calibration Factor
Numerical entry
Calibration Factor is defined as the number of pulses from flow sensor per one
gallon of fluid passing through the meter. This is the parameter by which the fac-
tory calibrates the flow meter. Change of this parameter is rarely needed by cus-
tomers. It is only necessary if you believe the PWE flow meter is no longer accu-
rate.
A typical display with Calibration Factor selection is shown below.
4.9.4 Submenu Flow Meter Measure Mode
Tabular entry
Signal Processing software algorithm can be set to calculate flow rate based on
two different methods:
a) number of pulses over preset measure interval
b) pulse width measurement
First method (a) was explained earlier (see Section 4.9.2). Second method (b)
allows get quick response time and best resolution of the flow rate, but with pul-
sating or especially noisy flow environment the stability of the flow rate reading
may be compromised. A digital filter (noise reduction algorithm) is available in
the flow meter when pulsating flow or especially noisy signals are encountered
(see Sections 4.9.5 and 4.9.6). The digital filter improves the displayed instanta-
neous flow values.
45
Measure Interval
4000 ms
Calibration-Fact
1366 Pulse/Gal
Note: Your PWE Flow Meter was calibrated at the factory for the
specified fluid and full scale flow range (see device’s label or calibration
data sheet). There is no need to adjust the Flow Meter calibration
factor, unless adjustment for specific installation or fluid is needed.
Any alteration of the flow meter calibration factor will VOID calibration
warranty supplied with instrument.
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