Vega VEGAPULS 67 Operating Instructions Manual page 39

VEGAPULS 67 • 4 ... 20 mA/HART - four-wire
•
Vessel:
– Lateral outlets and inlets
– Joins like flanges, weld joints
– Shifting of the running time in the tube
•
Process/measurement conditions:
– Condensation
– Buildup
– Separation of oil and water possible
– Overfilling into the antenna possible
•
Properties, sensor:
– Measurement speed optimized through little averaging
– Entering the tube inside diameter takes the running time shift
into consideration
– Echo detection sensitivity reduced
– False signal suppression recommended
Plastic tank:
•
Vessel:
– Instrument fix mounted or built in
– Measurement through the vessel top, if appropriate to the
application
– With empty vessel, the measurement can go through the bot-
tom
•
Process/measurement conditions:
– Condensation on the plastic ceiling
– In outdoor facilities, water and snow on vessel top possible
•
Properties, sensor:
– False signals outside the vessel are not taken into consideration
– False signal suppression recommended
Transportable plastic tank:
•
Vessel:
– Material and thickness different
– Measurement through the vessel top
•
Process/measurement conditions:
– Measured value jump with vessel change
•
Properties, sensor:
– Quick adaptation to changing reflection conditions due to ves-
sel change
– False signal suppression required
Open water (gauge measurement):
•
Rate of level change: slow level change
•
Process/measurement conditions:
– Large distance from sensor to water surface
– Extreme damping of output signal due to wave generation
– Ice and condensation on the antenna possible
– Spiders and insects build nests in the antennas
– Floating material and animals sporadically appear on water
surface
•
Properties, sensor:
– Stable and reliable measured values through frequent averag-
ing
6 Set up with the display and adjustment module
39