Farmer Chamber
Ionization Chamber
Type 30010, 30011, 30012, 30013
Operating Manual - Application
D596.131.00/05 en
15
Operate the detectors only in the rated ranges
of use indicated in section
. Other operating conditions may lead to
incorrect results.
HINT
Using the detectors with other electrometers
or within other rated ranges of use is the sole
responsibility of the user.
WARNING
High voltage is a source of risk.
Bodily Injury!
The combination of different connection sys-
tems to connect the detectors requires special
precaution. Connect high voltage only via an
active current limitation (I
max
< 0.5 mA).
When the detectors are properly connected, high
voltage is not applied to any of the exposed com-
ponents.
Connection cables with an overall length of up to
100 m can be used between the detectors and the
measuring device.
For measurements with
137
Cs,
60
Co or higher ener-
gies in air, always use the detectors with their
build-up caps. Performing the measurements with
these radiation qualities without build-up caps will
lead to incorrect results.
Air Density Correction
The detectors are vented and require air density
correction. The correction factor k
TP
for air density
correction is calculated according to the following
formula.
T
temperature in sensitive volume [°C]
P
atmospheric pressure at measuring
site [hPa]
T
0
calibration temperature 20 °C or 22 °C
P
0
atmospheric pressure for calibration
1013.25 hPa
Check the aeration for proper functioning by
comparison with other chambers or by using a
radioactive check device.
