Xylem photoLab 6600 UV-VIS - Manual (Page 40)

Operation photoLab
®
6600 UV-VIS
40 ba75848e01 08/2009
Validity of the zero
adjustment
The data of the zero adjustment is stored in the photometer separately for
each cell type. As long as the data is valid, it is automatically used again after
a temporary change to a different cell type. The validity depends on the
respective mode:
* After the wavelength or method respectively was temporarily exited the photometer
displays that a zero adjustment is available and the time it was carried out. You can then
decide whether to use this zero adjustment or carry out a new zero adjustment.
When to repeat the
zero adjustment?
We recommend to repeat the zero adjustment in the following cases:
z If the photometer was subject to mechanical stress such as strong shock
or transport
z If the ambient temperature changed by more than 5 °C since the last zero
adjustment
z At least once per week
z If a new cell type (different manufacturer, different glass type is used)
z Basically each time you want to measure with the highest possible
accuracy.
Mode Validity of the zero adjustment
Concentration (permanently
programmed methods) z Till the next zero adjustment
Absorbance / % Transmission z Till the next zero adjustment with the
same wavelength *
Concentration (user-defined
methods) and
Multi wavelengths
z Till the next zero adjustment for the same
method *
Kinetics z Till another kinetic profile is loaded
z Till the Kinetics mode is exited or the
photometer is switched off