IKA C 6000 isoperibol Package 2/12 - Manual (Page 37)

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„Check chart“ tab
This displays the graphics for the selected calibra-
tion with the upper and lower warning and con-
trol limits. The scaling is adapted automatically.
LWL/UWL and LCL/UCL
The LWL and UWL (lower and upper warning li-
mits) defi ne the area within which 95% of the
calibration measurements should lie.
The LCL and UCL (lower and upper control limits)
defi ne the area within which 99.7% of the cali-
bration measurements must lie in order for the
device to fulfi l statistical controls.
This means that if 5% of the points (one in twen-
ty) lie outside the warning limits or any points lie
outside the control limits, the calorimeter must
be verifi ed.
Calculation of the limits, where sigma = standard
deviation; sqrt = square root and N = number of
measurements:
UCL – mean value + 3 x sigma / sqrt(N)
UWL – mean value + 2 x sigma / sqrt(N)
LWL – mean value – 2 x sigma / sqrt(N)
LCL – mean value – 3 x sigma / sqrt(N)
If you click on „Show all“, all calibrations not just
those selected are shown in the graphics. This is
useful if there are several series of calibrations or
additional check calibrations. You can use the
check and warning lines to decide whether the C
value has shifted and therefore a reselection and
recalculation is necessary.
To exit this menu you must use the arrow keys to
switch to the „Decomposition vessels“ tab.
Exit with „Done“.
If you wish to print the check chart, press the
„Print“ button.
„New decomposition vessel“ tab
The „New decomposition vessel“ tab offers the
following options :
Use automatic decomposition vessel ID detec-
tion: automatic decomposition vessel detection
is an important precondition for safe working
with decomposition vessels. Deactivation is not
recommended but may occasionally be necessary
for repair purposes.
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