Operating instructions

METTLER TOLEDO DL36 13
Notes
1. Stirring and titration time
Run Run
Sample Stirring time t(stir) t(wait): no abort of t(max) or the time until defined
injection the titration drift stop is reached
No iodine generation Iodine generation
Automatic drift compensation Titration time for which you can select the type of
by internal calculation drift compensation (see page 14)
The titration time is printed out (Titr. time) if you select "GLP" for the report (see Section
7.3.2).
2. Abort parameters t(max) and drift stop
A defined titration time "t(wait) + t(max)" is suitable for titrations in which the end point is
reached only very slowly owing to side-reactions.
With t(max) = 0, the titration time depends on the drift stop.
A higher value for the drift stop shortens the duration of the titration, but leads to a larger
titration error, above all when the sample releases moisture only slowly.
• With oil samples, for instance, an increase in the drift can be observed. In this case, the
end point will not be reached if the drift stop value is too low.
• In the case of titrations with a sluggish approach to the end point as a result of side-
reactions, the magnitude of the error can be reduced by a higher drift stop value.
Titration curves with rapid and slow release of moisture with two relative drift stop values:
A: measured drift before the titration End point 1: with high drift stop value
L1: high drift stop value End point 2: with low drift stop value
L2: low drift stop value
The method
µg H
2
O/min
Start End point 1 End point 1
End point 2 End point 2
Start
L1
L2
A
t
Sample which
releases H
2
O
rapidly
Sample which
releases H
2
O
slowly