Operating instructions

42
8 Application examples
VEGAMET 625 • Double channel HART
28970-EN-150129
•
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specicationsasformeasurement
loop 1
– Measurementloop3(dierence):The adjustment of the
upstream water is taken over automatically (0 % ≙ 0.00m, 100%
≙ 2 m)
•
Relayconguration
– Selectunder"Measurementloops - Meas. loop 3 - Outputs -
Relay otuputs - Relay 3 - Overll 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dierenceof20cmandswitches
on again at 10 cm. Hence the cleaning procedure starts with a
gaugedierenceofmorethan20cmandisrunninguntilthe
dierenceisagainbelow10cm.
8.3 Interface measurement with VEGAFLEX
Inaninterfacemeasurement,therearetwodierent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conrm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 constant with [->]. The input vari-
ables 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 constant
– Enter here the exact dielectric constant of the upper medium.
ThisgureisthentransferredautomaticallytoVEGAFLEX.