ORTEC DSPEC Pro, Руководство пользователя по оборудованию

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794380D / 0914 1. INTRODUCTION
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1.7.1. SMART-1 HPGe Detector Construction
In the SMART-1 detector, the controller and high-voltage power supply are contained in a
single, small module and are permanently attached to the detector endcap. The cable is strain-
relieved and sealed. This eliminates the possibility that the detector will suffer severe damage
from moisture leaking into high-voltage connectors. The controller can be positioned in any
convenient place. It does not interfere with shielding or other mounting hardware.
1.7.2. Using Older Detectors
For older detectors, a detector interface module (DIM) is used. The DIM is a compact size and
can be attached directly to the detector itself, keeping the length of the high-voltage cable to the
absolute minimum. The DIM is only needed for non-SMART-1 detector use.
The DSPEC Pro uses the following DIMs for support of non-SMART-1 detector systems:
!
DIM-POSGE For any non-SMART-1, positive-bias, HPGe detector (includes short
leads with mating connectors for connecting to existing detector
cabling), +500 V to +5000 V.
!
DIM-NEGGE For any non-SMART-1, negative-bias, HPGe detector (includes short
leads with mating connectors for connecting to existing detector
cabling),
!
500 V to
!
5000 V.
!
DIM-POSNAI For any positive-bias NaI detector (includes short leads with mating
connectors for connecting to existing detector cabling), +100 V to
+1800 V.
!
DIM-296 For any positive-bias NaI detector (with Model 296 ScintiPack tube
base/preamplifier/bias supply for NaI detectors with 14-pin, 10 stage
photo multiplier tubes), 0 V to 1200 kV.
1.7.3. How State of Health (SOH) is Monitored
The SMART-1 HPGe detector SOH function operates as follows: When the acquisition is
started, the DSPEC Pro clears all the bits of the SOH byte in the SMART-1 HPGe Detector
memory. During data acquisition, the SMART-1 HPGe Detector monitors the conditions listed
above. Should any of these values fall outside a specified range (even if they subsequently return
to normal), the relevant SOH bit is set. The bits stay set until cleared externally with the
Acquire/Clear command in MAESTRO; or the firmware commands CLEAR, CLEAR_ALL, or
CLEAR_HV_ HEALTH. At the end of the acquisition, the DSPEC Pro reads the SOH and if any
bit is set, displays a warning message. If no bits are set, no message is displayed; this means