VEGA VEGAFLEX 86 4 … 20 mA_HART - four-wire Coax probe - Manual (Page 50)

50
7 Setup with PACTware
VEGAFLEX 86 • 4 … 20 mA/HART - four-wire
42285-EN-130314
Information:
In special cases you can change the medium type. This setting can be
changed under "Extended adjustment".
Application
In this field you can select the application you want to use your instru-
ment for. You have the following selection options:
•
Level in the vessel
•
Level in the bypass/standpipe
•
Interface in the vessel
•
Interface in the bypass/standpipe
•
Demonstration mode
Level measurement: If you select "Level", you can select the proper-
ties of the medium in another field.
Interface measurement: If you select "Interface", the instrument needs
more information, such as the distance to the interface, the dielectric
constant of the upper medium or whether or not there is a superim-
posed gas phase.
Demonstration mode: This mode is suitable for test and demonstra-
tion purposes. In this mode, the sensor ignores all logic parameters
and reacts immediately to all measured value changes within the
measuring range.
Application - Level measurement
The level measurement refers to the product surface which is the limit
to the gas phase.
•
Liquids
– Solvents, oils, LPG - dielectric constant < 3
– Chemical mixtures - dielectric constant 3 … 10
– Water-based - dielectric constant > 10
•
Bulk solids
– Dusts, wood chips - dielectric constant < 1.5
– Granules, dusts, powders - dielectric constant 1.5 … 3
– Cereals, flour - dielectric constant > 3
Application - Interface measurement
The interface measurement refers to the phase limit between two
liquids. The total level is also available as a measured value.
•
Superimposed gas phase present
– Check if there is a superimposed gas phase in the vessel. This
is always the case if the total level never touches the process
fitting.
•
Properties
– Here you can enter the dielectric constant of the upper medium
– As an alternative you can enter the distance to the interface
Adjustment for the level measurement
If you have selected level measurement in the previous menu, then
you can enter the values for the min. and max. adjustment. The value
to be entered refers to the distance from the sealing surface of the
process fitting (sensor reference plane) to the surface of the product.
Step 3 of 7
Adjustment