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Metrohm 916 Ti-Touch User Manual

Page 296

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28.1 Dynamic equivalence point titrations (DET)

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916 Ti-Touch

of the command). This value is used for temperature correction in pH
measurements.

Input range

–20.0 - 150.0 °C

Default value

25.0 °C

User-defined parameters
These parameters are only accessible when Titration rate = user.

Meas. point density

A small value means small volume increments, i.e. a high measuring point
density. The curve then shows all the finest details which also include
noise; this could cause unwanted equivalence points to be found. A larger
value, i.e. a smaller measuring point density, permits quicker titrations. If
you are using a dosing device with a small cylinder volume then a smaller
measuring point density value may be beneficial. However, you should
also set a smaller signal drift and a higher EP criterion at the same time.

Input range

0 - 9

Default value

4

Min. increment

This smallest permitted volume increment is added at the start of the titra-
tion and with steep curves in the region of the equivalence point. Very
small values should only be used if a low titrant consumption is expected;
otherwise unwanted equivalence points could be evaluated.

Input range

0.05 - 999.90 µL

Default value

10.00 µL

Max. increment

A maximum volume increment should be selected in the following cases:

when titration consumption is very low up until the equivalence point
is reached.

when a start volume is dosed up until shortly before the equivalence
point is reached.

when the change of direction in the jumping range is very abrupt,
because otherwise it could easily happen that an excessively large vol-
ume will be dosed in the region of the equivalence point.

The value should not be less than 1/100 cylinder volume.

Input range

0.1 - 9999.9 µL

Selection

off

Default value

off