BERTHOLD TECHNOLOGIES LB 480, Руководство пользователя

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SENSseries LB 480 Level measurement
BERTHOLD TECHNOLOGIES GmbH & Co. KG
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Volume 3 Menu Structure
3
2.20
Cal Parameter
Menu path: Device Config

Setup

Cal Parameter .
In this menu you can calibrate and adjust the measuring system
and set the parameters needed to perform the measurement.
Readjustment of an already calibrated measurement:
The count rates in this menu and the submenus are not decay com-
pensated
1
. For this reason, after several weeks the calibration char-
acteristic curve cannot be changed using data from Cal
Parameter ; rather, it must be changed using the values from
Meas Parameter . These values correspond to the data the LB 480
is currently using to run measurements. The data in Meas
Parameter also include the decay compensated count rates of the
calibration points which were used last to calibrate the LB 480.
Select
Recall to obtain the decay compensated values. The current
values from Meas Parameter ( Device Config

Meas
Parameter ) are copied back here.
IMPORTANT
Changes in these parameters have an influence on the measure-
ment only when you select the
Calibrate command.
1 Cal Points
Opens the menu for the calibration ( page 3-337 ).
2 Cal Settings
Opens the menu for entering the basic detector-specific settings
that needs to be performed before calibration (
page 3-341 ).
3 Product Conditions
Opens the menu for entering the basic product-specific settings that
needs to be performed before calibration (
page 3-343 ).
4 Cal Comp Factor
 Visible only if Compensation Mode is set to AUTO GPC .
You need this menu if you want to find the Comp Factor, because
the standard
Comp Factor = 1 is only valid when the measuring
system utilizes the beam path to 45 degrees. The more you deviate
from it, the more important it is to determine the Comp Factor your-
self. This requires that you pressure up the container and read in
the count rates at different pressures. The larger the pressure range
in which measuring points are recorded and the more points you
record, the more accurate will be the
Comp Factor later.
5 Adapt Calibration
The menu contains functions to adjust the characteristic curve and
to take over older calibration data.
1. Each source will lose activity over time and become weaker; this is called source decay. For this rea-
son, the count rate measured at the detector decreases in the course of time. The process can be
calculated using a mathematical function and is automatically compensated for by the SENSseries de-
tectors.