wtw PhotoLab Spektral, Руководство по эксплуатации

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20
3 Commissioning
→
To switch off the photometer, close the cover.
After 5 seconds:
Automatic change to the concentration measuring
mode
The AutoCheck function automatically
checks and calibrates the optical measur-
ing unit. To do this, the photometer per-
forms cyclical measurements without a cell.
The photometer checks whether the signal
level of the optical unit in the meter lies with-
in the allowable tolerances. Furthermore,
the photometric zero point of the meter is
calibrated.
After the warm-up time, the first AutoCheck
is performed as part of the SelfCheck. From
this point in time, the AutoCheck is repeat-
ed every 5 minutes as long as no cell is in-
serted in the cell shaft. If an AutoCheck
cannot be performed because a cell is in-
serted, it is automatically repeated as soon
as the cell is removed.
During the measurement of the kinetic (see
section
10.2 K
INETICS
), the photometer
cannot perform an AutoCheck due to the in-
serted cell. Thus, you must wait for a warm-
up period of 2 hours in this case.
After this time, the stability of the signals is
so high that the measuring accuracy is re-
tained over longer periods of time even
without an AutoCheck.