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Metrohm viva 1.0 Manual User Manual

Page 483

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5 Method

viva 1.0

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471

Measurement
Two types of measurement can be selected from, Measurement with
drift control
or Measurement without drift control.

Selection

Measurement with drift control | Measure-
ment without drift control

Default value

Measurement with drift control

Measurement with drift control
The measurement is carried out drift-controlled if this option is
selected. The measurement is canceled as soon as the defined Signal
drift
or the Stop measured value is reached or the defined Max.
waiting time
has expired. The corresponding parameters are not visi-
ble if this option is disabled.
Measurement without drift control
The measurement is carried out without drift-control if this option is
selected. Measurement is continued for as long as one of the two stop
criteria Measuring time or Stop measured value is fulfilled. The
corresponding parameters are not visible if this option is disabled.

NOTE

A constant measured value is often only reached after a certain time, as
mixing and possibly the reaction itself require a certain time. The
response time of an electrode can also increase with time, i.e. reaching
a constant measured value takes longer and longer. Drift-controlled
measurement
is particularly advisable in such cases, as the measured
values are not applied until equilibrium has almost been reached.

Measurement with drift control
If the option Measurement with drift control has been selected, then
the following parameters will be displayed:

Signal drift

The measured value is only accepted if the signal drift defined here has
been fallen short of.

Input range

0.1 - 999,000 mAU/min

Default value

1.0 mAU/min

Min. waiting time

The measured value is not accepted until the minimum waiting time has
elapsed, even if the signal drift has already been reached. The drift contin-
ues to be checked while the waiting time is elapsing.