BERTHOLD TECHNOLOGIES LB 480, Руководство пользователя

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SENSseries LB 480 Level measurement
BERTHOLD TECHNOLOGIES GmbH & Co. KG
3 – 345
Volume 3 Menu Structure
3
• MANUAL GDA (Gas Density Adjustment)
If the container in operation is under gas pressure (> about 2
bar) and the calibration cannot be carried out under operating
pressure, then it is possible to calculate in advance the count
rates that should be obtained under operating pressure. Addi-
tional parameters are displayed which are required for the com-
pensation.
–
Gas measuring path
– Setup Gas Density
– Gas Density at Op
Please note that with a multi-point calibration the GDA can only
be used when the same gas density is available at all calibration
points during calibration. Only the calibration point at 100% is
excluded, provided that the measurement path in the container
is completely filled with product.
• AUTO GPC (Gas Property Compensation)
IMPORTANT
This function requires special knowledge and should be enabled
only by a Berthold service engineer, or by a specially trained per-
son.
If the vessel is in operation under gas pressure (> about 2 bar)
and the gas pressure is not constant, then a continuous gas
density compensation is advisable. An additional measurement
is required which is arranged above the liquid level measure-
ment and constantly measures the gas density in the container.
Additional parameters required for this calibration appear on
the Calibration menu.
A further prerequisite for GPC is that the source used for level
measurement as well as for compensation measurement con-
tain the same isotope. This means, if a level measurement is
carried out using Cs-137, then the compensation measurement
must also be carried out with Cs-137.
GPC cannot be used for a level measurement with point source
and point detector.
4 ... 20 mA
HART
Detector for GPC
compensation
measurement
RS 485
Detector for level
measurement