Berthold DUO XPERT LB 470RID, Operating Manual

Page: 105 / 240

LB 470RID Level 7 Main Menu Device Setup
56925-1BA2 Rev.02, 05/2021
105
Calibration Settings: Background
Device Setup | Setup | Calibration | Calibration Settings
The background count rate (Fig. 76, item 1) is the natural background radiation
seen by the detector and must be measured at least for rod detectors. This count
rate is compensated for by the system. The best approach for your background
measurement is dependent on the situation on site and on the type of radiation
source.
NOTICE
A closed shield also results in measurable residual radiation, which can falsify the
measurement of background radiation. For this reason, it is recommended that
the detector (Fig. 75, item 4) be determined at a suitable distance (approx. 10 m)
or behind a thick concrete wall (Fig. 75, item 2).

In the case of measuring arrangements with point sources, it is recommended
to place the shield with spotlights at a suitable distance (approx. 10 m), or
behind a thick concrete wall.

To avoid calibration errors, it must be ensured that during calibration and
commissioning of the measuring equipment no welding tests are being done
on the site, even at long distance.
1
2
3
4 Radiation shield (closed)
Concrete wall
Distance
Rod detector
Fig. 75 Conditions during background determination
IMPORTANT
All entries and changes in the “Parameters” tab will take effect only when you
click on the <Calibrate> button in the submenu “Calibrate”.