ORTEC Detective X, Руководство пользователя

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ORTEC
®
Detective
®
X Handheld Radioisotope Identifier 1107231N / 082020
16
and expels warm air through a vent on the bottom. Components inside the plenum (including the cooling
fan) are tightly sealed against water and dust ingress. With an IP 65 rating, the Detective X can be used even
in heavy rainfall.
A pressure equalization breather is located on the bottom of the instrument to ensure excessive air pressure
does not build up inside the unit at high altitudes, as might be encountered during air transport.
The speed of the cooling fan increases under high heat conditions such as when initially cooling the detector,
decreases under normal conditions, and turns off completely at low ambient temperatures.
Adequate airflow over the cryogenic cooler is important for efficient cooler operation. Always ensure the air
can flow freely through the instrument. Failing to do so will result in excessive battery usage and excessive
time to initially cool the detector. Never block the air inlet at the back of the unit or the exit vent on the
bottom of the instrument. Be aware that placing the unit on a soft surface such as a sofa or even a thick
carpeted floor can result in the bottom air vent becoming blocked. It is best to set the unit on its side when
resting it on soft surfaces.
2.6 COLLIMATORS (GREEN AND PEACH)
ORTEC offers two standard collimators for the Detective X:

DETECTIVE-X-ACC-COL-ST 4mm Stainless Steel (colored green; see Figure 24)

DETECTIVE-X-ACC-COL-W 4mm Tungsten (colored peach)
Collimators reduce sensitivity of the instrument to radiation sources not
directly in front of the instrument, enhancing the unit’s ability to locate a
radiation source.
Both use the magnetic mounting system used for the passive detector cover
and the neutron detector, so they are easy to install and remove. Both also
mate via a connector (Figure 19) that is read by the Detective X software to
determine collimator type. That information is added to the N42.42 files, and
the correct ambient background file is used. Note that before first use of a
collimator, an ambient background measurement must be taken with that
collimator installed (see Section 4.14). Until this background has been ran,
the status area on the screen will say “No Background.”
The tungsten collimator is the most effective of the two because tungsten is
more than twice as dense as stainless steel. Unfortunately, this also means
the tungsten collimator is more than twice as heavy, so it may not be as
convenient to use in the field.
2.7 LOW-ENERGY FILTER (RED)
A low-energy filter is offered for applications where it is important to identify radioactive materials in the
presence of very high levels of low-energy gamma rays. This situation often occurs with aged plutonium due
to ingrowth of americium. The filter allows the plutonium to be correctly identified even in the presence of
high levels of americium that would otherwise produce an overrange alarm (see Section 4.5).
Figure 24. Stainless Steel
Collimator