wtw PhotoLab Spektral, Operating Instructions Manual

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13 User-defined methods
Selecting input zero point and slope:
Selecting calculate zero point and slope:
When entering user-defined methods, the photometer
offers the option to measure/input and store the char-
acteristics in a single step. In doing so, minimum 3 up
to maximum 10 standard solutions are measured;
from these, the photometer determines the slope and
zero point of the new method.
At this point, the photometer provides practical default
values for the AQA theoretical value and tolerance.
They can be overwritten using the numeric keypad.
→
Confirm each time using .
→
Use to select between
●
input zero point and slope
●
calculate zero point and slope.
→
Confirm with .
→
Input the zero point and slope
→
Select the sign (+/–) using
– Numbers from 0 to 9
– Confirm each time using .
→
Press and input the concentration of the first
standard solution, e. g. 100 mg/l.