VEGA VEGAMET 625 - Manual (Page 42)

42
8 Application examples
VEGAMET 625 • Double channel HART
28970-EN-130701
•
Adjustment
– Measurement loop 1 (upstream water): Select under
"Measurement loops - Meas. loop 1 - Adjustment" in the menu
item "Adjustment unit" the unit "m" (meter) and the density
unit "1.000 kg/dm³". Enter under "Min. adjustment" 0.00 m and
under "Max. adjustment" the max. level in meter (h1) ein. I.e. in
the existing example 2 m
– Measurement loop 2 (downstream water): Carry out the
adjustment with the same specifications as for measurement
loop 1
– Measurement loop 3 (difference): The adjustment of the
upstream water is taken over automatically (0 % ≙ 0.00m, 100%
≙ 2 m)
•
Relay configuration
– Select under "Measurementloops - Meas. loop 3 - Outputs -
Relay otuputs - Relay 3 - Overfill protection - Percent" the menu
item "Switching points relay 3". Enter for switching point "OFF"
10 % and for switching point "ON" 5 %. With these settings,
the relay deenergizes at a difference of 20 cm and switches
on again at 10 cm. Hence the cleaning procedure starts with a
gauge difference of more than 20 cm and is running until the
difference is again below 10 cm.
8.3 Interface measurement with VEGAFLEX
In an interface measurement, there are two different media which
do not mix, e. g. water and oil or solvents. To detect the volume of
both products, it is necessary to detect the height of the upper liquid
(level) and the interface between the two products. A VEGAFLEX is
necessary as a transmitter which delivers the distance to the upper
medium as well as the distance to the interface. Via the adjustment in
VEGAMET 625 the level, interface and layer thickness of the upper
medium can be calculated and displayed.
The following steps are necessary:
•
Selection of the application
– Select under "Device settings - Application" the entry "Inter-
face measurement" and confirm with [OK]. Via the [->] key you
reach the next step.
•
Assignment of the inputs and measurement loops
– Select "Input - Change input". Now the automatic sensor
search is started and if connected correctly, VEGAFLEX will be
displayed. Take over the selection with [OK] and move to the
adjustment of the dielectric figure with [->]. The input variables
are assigned automatically to the following measurement loops:
– Meas. loop 1: Interface (level of the lower medium)
– Meas. loop 2: Level (total level of both products)
– Meas. loop 3: Layer thickness (thickness of the upper medium)
•
Enter dielectric figure
– Enter here the exact dielectric figure of the upper medium. This
figure is then transferred automatically to VEGAFLEX. Further
information on the dielectric figure are available in the operating