BERTHOLD TECHNOLOGIES Uni-Probe LB 490 - Replacing the Plastic Scintillator

Uni-Probe LB 490
BERTHOLD TECHNOLOGIES GmbH & Co. KG
2 – 229
Volume 2 4 Repair, Maintenance and Service
2
4.9 Replacing the Plastic Scintillator
Explosion hazard!
Spare parts for detectors used in hazardous areas may only be
installed by BERTHOLD TECHNOLOGIES service personnel or by
persons authorized by BERTHOLD TECHNOLOGIES. If this is not
possible, the complete detector has to be replaced or returned to
the manufacturer for repair.
When replacing the multiplier it may happen that the sensitivity of
the detector to Gamma radiation changes. Therefore, check the
level indication with empty and full vessel after replacement and, if
necessary, carry out a new calibration.
IMPORTANT
BERTHOLD TECHNOLOGIES recommends having the plastic scintil-
lator replaced by trained personnel only, see Volume 1,
"3 Qualification of Personnel". The wrapping of the plastic scintilla-
tor must not be opened or torn .
 Dismantle the electronics module as described on page 2–222.
 Undo the two nuts (6) on the scintillator fixture.
Figure 4-5 Fixture for rod detector
 Carefully pull out the fixture and the plastic scintillator.
 Carefully insert the new plastic scintillator into the pipe and fix
it with both nuts (6).
IMPORTANT
Before reassembling the scintillator fixture with the plastic scintilla-
tor, apply a drop of pure silicon oil to the center of the plastic win-
6