User's Manual

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1010NFM-3JSection 2
2.7.3 CALIBRATE FLOW RATE
The 1010’s intrinsic calibration is excellent as confirmed by numerous laboratory and field trials under
diverse application conditions. We thus can confidently say that in any given application, the majority of
conventional flowmeters can not match the system’s measurement range or its linearity. Some appli-
cations may require an output adjustment to match an official external reference. The Calibrate Flow
Rate menu allows you to select a calibration mode. The right-hand column shows the active calibration
mode. You can select Intrinsic (factory), Kc (Slope Correction) or Multipoint (Non-linear) Calibration.
Selecting either of the external calibration modes will not eliminate the Intrinsic (factory) calibration. You
can use this menu cell to switch between Intrinsic, Kc or Multipoint at any time.
Kc Calibration
For most applications, the measured flow range produces a linear meter response. Therefore, the Kc
(slope correction) calibration is the preferred method since it only requires a single correction factor for
all the flow rates encountered. Changing the calibration can cause profound changes in a flowmeter’s
operating characteristics. Use only the most respected flow standard to obtain a correction factor. The
percentage you enter must provide an accurate and consistent shift across the entire flow range
anticipated for the application.
To obtain the Kc factor, compare flow total data taken simultaneously from the 1010 and a reference
meter whose accuracy meets the required standard. Allow both meters to accumulate flow total data
long enough to average out any differences due to flow fluctuation between the two meter locations.
Compare outputs of the two totalizers to determine percentage increase (+) or decrease (-) that is
necessary to produce the best average correlation between System 1010 and the reference standard.
For example, entering [-0.29] will produce a reduction of 0.29% in the calibration at all flow rates.
NOTE: Always enter the + or - sign first.
To calculate Kc:
To enter the Kc Factor:
To enable numeric entry press .
Use the numeric keys to enter the required Kc (as calculated above). Note that the Kc value
can be negative or positive. Enter the - or + sign first, then type in the calibrated value.
To store the data press .
Note that Kc now appears in the right-hand column of the [Calibrate Flow Rate] menu cell with
its new value. Also note that this Kc value can be viewed on the site printout.
MultiPoint Calibration
MultiPoint calibration serves applications that require a non-linear meter calibration. You can enter
correction factors for up to ten significant points over the entire measurement range. This is accom-
plished by:
(a) Selecting up to 10 separate calibration points by entering a raw (un-calibrated) flow rate.
(b) Entering a negative or positive correction for each calibration point that you select.
ENT
Kc =
x 100
Actual Rate
Indicated Rate
-1
Kc =
x 100