Polimaster BDG1-PM1403, Руководство по эксплуатации

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6.4.4.1 Detection of gamma RS
To detect gamma radiation sources (further RS) BDG1 should be placed so that the
graduation direction (Figure 4.2) of the built-in detection unit coincides with the direction to the
tested object. The closer the effective center of the BDG1 detector is placed to the object under
examination (luggage, person, container, vehicle, etc.) and the slower it moves alongside the object,
the higher the RS detection rate will be.
Use light alarms and watch LCD indication to detect RS in noisy environments (BDG1 sound
(audio) signals might not be heard)).
Instrument sensitivity and false operation rate depends on:
- set
n
coefficient;
- background level calculated by BDG1 in calibration mode.
Since natural radiation background level fluctuations can be significant, calibrate instrument
to background level just before starting detection of RS (11.1.2).
Note, that the instrument during misoperation emits nonsystematic light and sound alarms.
Such alarms can be easily differed form the signals emitted by the instrument when RS are detected
(the signals are characterized by constant repetition rate). The rate increases when RS gets closer to
the instrument.
Start RS localization when RS is detected or there is some indication of possible RS presence.
6.4.4.2 Localization of gamma RS
To localize RS: place BDG1 near the tested object at a distance of no more than 10 cm.
Move the instrument alongside the object no faster than 10 m/s. The closer RS is, the faster the
signals repetition rate is.
Sound (audio) signals, accompanied by blinking blue ("ALARM") LED, are heard when
sound (audio) alarm function is switched on.
When frequency of light and sound (audio) alarms becomes extreme (right up to continuous
light and sound signal), further localization procedure is possible only after the instrument is
calibrated to new gamma background level. To do this, keep the same distance to the object (if
possible) and switch to the calibration mode. The instrument will enter the mode of calibration by
gamma background level. BDOI LCD can show message warning that the calibration process may
take some time. In this case user should decide whether to interrupt the calibration process. After that
the calibration to new gamma background level is completed the RS localization procedure can be
continued.
6.4.5 PC communication mode
BDG1 enables information exchange with PC running under WINDOWS. Operation
sequence for working in the mode of communication with PC by USB or RS-485 interface is given in
the “Help” file of the current program. Do the following to enable BDG1 operation in the PC-
communication mode:
- install user program from the supplied CD onto the PC;
- connect BDG1 to PC using the USB-cable;
- start user program;
- PC takes control over BDG1.
Working with PC is described in the annotation.