ORTEC Micro-Detective-HX, Руководство по эксплуатации

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ORTEC Micro-Detective
®
-HX Human Portable Radiation Detection System — Operation Manual
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This is not to be confused with a vacuum leak, although both result in a degradation of the vacuum.
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Headphones ( ) Rear-panel female connector, with dust cover, accepts standard male
headphone jack. Headphone volume controllable from the HX touchscreen. Note that the audible
high-dose-rate alarm sounds whether or not headphones are connected to the HX. This alarm is
not routed through the headphones and its volume is independent of the headphone volume
setting.
C.3. PC Prerequisites
In addition to completely independent, standalone operation, the HX can also be operated as a
benchtop MCA, in conjunction with ORTEC C
ONNECTIONS
-32 software such as GammaVision,
by connecting it to any PC running 32-bit Microsoft Windows 7, XP Professional SP3, or 2000
Professional SP 4.
C.4. Long-Term Shutdown/Storage
This instrument uses a Stirling cycle refrigerator and all-metal-sealed cryostat designed for long
operational life. The vacuum integrity inside the cryostat is maintained by “getters,” which
scavenge traces of residual material when cold; and by an ion pump that operates when the
instrument is powered up. These two techniques maintain the system vacuum in peak condition
during normal use. A good vacuum yields rapid cooldown and ensures operation at the high end
of the instrument’s operating temperature range.
Over time, in any cryostat system, residual contaminants can be released from the materials
inside the evacuated cryostat by a process called outgassing.
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It has become apparent that, in
extended storage, the vacuum in our mechanically cooled identifiers may degrade to the point
that, on trying to restart, the gas load inside the cryostat is too high and the unit fails to cool. The
remedy is reasonably straightforward, if inconvenient: a “pump and bake” of the instrument is
required at an ORTEC service center. Fortunately, you can easily avoid this problem:
We strongly recommend that instruments used only occasionally be turned on once a month,
fully cooled to Ready status, and allowed to run for at least 48 hours. Doing this starts the ion
CAUTION
This instrument should be cooled and brought to operational status (
Status: Ready
) for at least
48 hours every month. Failure to do this may result in degraded performance or cooling system
failure.