IKA C 6000 isoperibol Package 2/12 User Manual

Page 37

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37

„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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