13
The processor counts the value of
the gamma channel operation threshold
Operation threshold = N + n *
N
N – average speed of counting impulses over the calibration time
n
– number of mean square deviations (
n
factor of the gamma channel).
n
factor changes the value of
the operation threshold
(the minimum detection level), the less
n
factor, the less threshold value is and the higher indicator sensitivity is.
n
factor is set by the user in the
mode of settings, if this is permitted in the communication mode with PC by the user-administrator (the
manufacturer sets the value of n factor equal to 5,3). The range of factor setting is equal from 1 to 9,9 with
discreteness 0,1.
For recalibration of the indicator by the background level the
MODE
button should be pressed (to
be kept pressed for more than 2 s), until “CAL” message is indicated on the LCD, then the push button
should be released. The analogue scale will also be indicated on the LCD along with the number of segments
increasing in time.
The automatic calibration function may be switched on in the mode of communication with the PC.
Automatic calibration makes it possible to automatically retain the high sensitivity at reduction of the
background level and avoid false operations with its slow increase.
After calibration completion the indicator is automatically shifted to the operating mode in
accordance with the chart of orders (see attachment
А
).
SEARCHING MODE.
DETECTION AND LOCALIZATION OF SOURCES OF GAMMA AND NEUTRON
RADIATIONS.
Being in the searching mode the indicator shows the speed of counts of the gamma channel in the LCD
upper line, s
-1
.
The following is indicated in the lower line:
РМ
1703
М
-
О
1
РМ
1703
М
-
О
1
А
РМ
1703
М
-
О
РМ
1703
МА
РМ
1703
МВ
•
the average statistical indication error of the average count
of gamma radiation in per cents;
РМ
1703GN
О
РМ
1703GN
А
РМ
1703GN
В
•
the average speed of count of neutron radiation in s
-1;
All modifications
•
If at indicator operation in the searching mode the average
speed of count of the gamma channel exceeds the upper
limit of indication,
"OL"
is indicated on the LCD
.
РМ
1703GN
О
РМ
1703GN
А
РМ
1703GN
В
•
If at indicator operation in the searching mode the average
speed of count of the gamma channel exceeds the upper
limit of indication, “999" blinking message is indicated on
LCD.