Siemens SITRANS F - Multipoint Calibration

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1010ENFM-3B
Section 2
MultiPoint Calibration
MultiPoint calibration serves applications that require a non-linear flowmeter calibration. You can enter
correction factors for up to ten significant points over the entire measurement range. This is accom-
plished by:
zSelecting up to 10 separate calibration points by entering a raw (uncalibrated) flow rate.
zEntering a negative or positive correction for each calibration point that you select.
Like the Kc slope correction described previously, you locate critical flow rate points by comparing flow
total data taken simultaneously from the FUE1010EN and a reference meter whose accuracy meets the
required standard. Again, it is important to note that you must allow both meters to accumulate flow total
data for long enough to average out any differences due to flow fluctuation between the meter locations.
Compare the two flow total readings to identify up to ten separate points (termed raw flow rates) where
there are significant deviations between FUE1010EN and the reference meter. Calculate correction fac-
tors (either negative or positive percentages) for up to ten points along the flow range. For example,
entering [-0.1] for point 1 produces a negative 0.1% change in the meter output whenever the system
measures the raw flow rate specified for point 1, etc. The valid range for each percent correction is from
-50% to +50%. If you enter a value outside of this range, the flow computer will set the calibration factor
to the nearest limit.
Use these to match FUE1010EN’s output with the reference meter’s response curve. Selected calibra-
tion points must increase in magnitude from point 1 to point 10 (or the last point that you wish to
calibrate).
NOTE: You must enter the raw flow rates in ascending order.
To perform a MultiPoint Calibration:
To access the [Calibrate Flow Rate] option list press
Move the cursor up to [MultiPoint], then press
ENT
This selects the MultiPoint calibration screen, which shows:
Point # (point #1 selected)
Indicated Rate (shows current rate for point #1)
% Correction (amount of correction applied either (-) or (+) percentage)