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 2 4 Repair, Maintenance and Upkeep
2
4.5
Checking the Detector
Scintillation counters do not include any wearing parts and their
service life is not limited, provided they are used under normal
operating conditions. Malfunctions or aging in the scintillation
detector can only be caused by excessive mechanical or thermal
stress.
Scintillation counters are used as detectors, since only these detec-
tor systems provide the required high sensitivity to Gamma radia-
tion and their service life is independent of the intensity of the radi-
ation field.
The number of light flashes per time unit is a measure of the inten-
sity of the radiation field. The individual flashes of light are very
short, so that a high resolution is obtained; this detector can be
employed for high count rates.
The flashes of light are converted into electrical signals in a photo-
multiplier (PMT), which is optically coupled to the detector.
Fig. 4-2 Scintillation detector
The point detector CrystalSENS uses a 50/50 NaI crystal as a scin-
tillator, the SuperSENS detector uses a 150/150 scintillator.
Radiation Scintillator Amplifier Dynodes
Light flashes
Photo cathode