KROHNE CORIMASS G-MFM 4085 EN - Manual (Page 22)

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3.2 Initial Start-up
•
Please check that the power supply corresponds to the information supplied on the data
plate.
•
Switch on the power supply.
•
On switch-on, the signal converter first carries out a self-test. The following sequence is
displayed:
TEST
10 G GX.XX
Primary Head Software Version
STARTUP
Mass flow will be displayed following a brief settling phase for the primary head.
•
For stable and accurate mass flow results the following should be checked:
a) The quality of the mechanical installation. See Sect. 1.2.2.
b) A good zero point calibration should be done. See Sect. 3.4. Further information
regarding zero point calibration can be found in Sect. 5.
3.3 Installation factor
The extensive self-diagnosis functions of the MFM 4085 also include a so-called installation
factor. This factor indicates whether the flow meter has been correctly installed in the pipeline
and whether the mounting supports have been fitted at defined points. For that reason, the
installation factor must without fail be checked during the initial start-up phase. The installation
factor can be checked by way of the keystroke combination as in Sect. 1.2.3.
If correctly installed, the value of the installation factor when the primary head is full of water
should be as per table in section 1.2.3. If the figure is higher, the specified accuracy of the flow
meter cannot be guaranteed. Please check the installation again on the basis of the installation
information (Sect. 1.2). If necessary adjust clamping with the meter displaying the installation
factor to obtain optimum performance.
3.4 Zero point adjustment
After installation adjust the zero point. To do this, the primary head must be completely filled
with the liquid product without gas or air inclusions. This is best obtained by allowing the
liquid product to flow through the primary head for approx. 2 minutes at a throughput rate of
greater than 50% of rated flow. Subsequently ensure that flow comes to a complete stop in the
primary head (see fig 10, Section 1.2) for setting the zero without interruption to product flow,
use a bypass set-up as shown in fig. 11 (Section 1.2). For best results the zero adjustment
should be performed with the front cover in place. To activate the calibration, use the bar
magnet provided to operate the magnetic sensors on the display.
A minimum warm-up time of 30 minutes is recommended to
ensure stable measurement operation.