VEGA FIBERTRAC 31 Foundation Fieldbus User Manual
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6 Set up with the display and adjustment module
FIBERTRAC 31 • Foundation Fieldbus
41780-EN-131119
The natural radiation on earth influences the accuracy of the meas-
urement.
With this menu item the natural background radiation can be faded 
out.
For this purpose, the FIBERTRAC 31 measures the natural back-
ground	radiation	and	sets	the	pulse	rate	to	zero.
In the future, the pulse rate from this background radiation will be 
automatically deducted from the total pulse rate. This means: only
the component of the pulse rate originating from the source will be
displayed.
The source container must be closed for this setting.
In this menu item you can select the temperature unit.
in this menu item you can select if you want to carry out a single or
double point adjustment on the sensor.
With the double point adjustment, the Delta I value is selected auto-
matically.
We recommend selecting the double point adjustment. To use this, 
you must be able to change the level of the vessel so as to carry out
the adjustment of the sensor with full status (covered) and with empty
status (uncovered).
Hence, you will get a very reliable switching point.
With	single	point	adjustment,	you	have	to	define	the	difference	
between the min. and max. adjustment points (Delta I) yourself during
the following setup.
This menu item appears only if you have selected "Single point
adjustment" as adjustment mode (Setup/Adjustment mode).
In this menu item you determine the point at which the FIBERTRAC 
31 should switch in uncovered status.
Setup - Background
radiation
Setup - Unit
Setup - Adjustment mode
Setup - Adjustment
uncovered (single point
adjustment)