Calibrate Flowrate; Kc Calibration - Siemens SITRANS F Operating Instructions Manual

Section 2
To Enable (or Disable) the Makeup Latch:
To access the [Makeup Latch] option list press
Move the cursor to select either [On or Off] by pressing
To turn Makeup Latch [On] or [Off] press

2.7.3 CALIBRATE FLOWRATE

Numerous laboratory and field trials under diverse application conditions have confirmed that System
1010's intrinsic calibration is excellent. We are thus confident that in any given application, the majority
of conventional flowmeters can not possibly match the system's measurement range or its linearity.
However, some applications may require an output adjustment to match an official external reference.
The "Calibrate Flowrate" 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, as a reference, to obtain a
correction factor. The percentage you enter will 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.
Kc =
To calculate Kc:
Kc =
To enter the Kc Factor:
To enable numeric entry press
Use the numeric keys to type the required Kc (as calculated above). Note that Kc value can be
negative or positive. Enter the - or + sign first, then type in the calibrated value.
To store the data press
[Calibrate Flow Rate] menu cell with its new value. Also note that this Kc value can be viewed
on the site printout.
Actual Rate
x 100
Indicated Rate -1 x 100
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. Note that [Kc] now appears in the right-hand column of the
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