Polimaster PM1401MA, Руководство по эксплуатации

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NOTE : The instrument can also adjust to gradually changing levels of gamma-radiation
background automatically to make operation with the unit more convenient. By default this
function is enabled by the manufacturer.
False alarms
Occasionally, the instrument may produce random “chirp” signals, called “false
alarms”. Such alarms (visual, audible and/or vibration) are irregular and can, therefore, be
easily distinguished from true alarm signals produced by the gamma radiation sources that
have continuous repetition rate and/or increase as the instrument moves closer to radiation
source. The number of false alarms depends on many factors including changes in the
ambient background radiation level as well as changes to the system setup.
2.4.2. Measurement mode
In the measurement mode the instrument displays the current value
of gamma radiation dose equivalent rate in μSv/h or mSv/h (μR/h or mR/h),
while the lower line indicates the average statistical error of the measured
value in %. In this mode the instrument alarms only if the safety threshold is exceeded and
does not adjust alarms to the changing background.
NOTE
: The PM1401MA is calibrated in collimated Cs-137 radiation only, thus, its readings
in measurement mode may differ from that of energy compensated dosimeters.
2.5 Low battery indication
When the battery voltage drops below critical value (1.1 volts), the instrument LCD will
indicate a blinking low battery sign and alarms will go of (audio, light and/or vibration). By
pressing the MODE button
the user can switch off the “critical low battery” warning for
about 30 minutes. At the same time the alarm thresholds will remain turned on.
NOTE: The instrument can work several hours after the critical low battery warning .
However it is highly recommended to replace the battery as soon as possible in this case.
2.6 Safety Alarm Threshold
The PM1401MA is equipped with Safety Alarm threshold to alert user when
immediately dangerous for life radiation level is reached. When this threshold is exceeded,
the instrument will produce easily distinguishable periodic audio and/or vibration alarm with
one-second interval.
The manufacturer’s preset value of Safety Alarm threshold is 30 µSv/h (3000 µR/h). If
necessary the Safety Alarm threshold can be set using PM1401MA User Software using IR
adapter.