Owner manual

5.7.3 Alphabetical instruction list
746 VA Trace Analyzer / 747 VA Stand
5-223
DCTMODE Page: O, S Stand: M, A Abbreviation: D
Instructions t/s Main parameters Auxiliary parameters
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## .. DCTMODE ..... t.step ........s t.meas ........ms
Function Measurement mode for direct current voltammetry
(DCT = Direct Current Tast).
Application Direct current voltammetry is the classic, simplest VA method with limited
sensitivity. It is mainly used for the investigation of reversible redox
systems.
Parameter Range; Default value / Meaning
t.step 0.05...9.9 s; 0.3 s
Time interval for voltage step
Time interval after which the voltage in the sweep is increased or
decreased by the amount U.step.
The following condition applies to the definition of t.step:
t.step > t.meas + t.drop + 30 ms
t.meas 1.0...64.0 ms; 40/50 ms for 50/60 Hz
Measurement time
Time during which the current measurement takes place. Measurement
is performed at the end of the time interval t.step.
Description With the DCTMODE measurement mode, the direct voltage applied to the
working electrode is continuously changed and the resultant current I
which flows measured as a function of the voltage U. The nature of the
measurement is shown below using the SMDE as an example.
Adjustable parameters:
DCTMODE
t.step
t.meas
SWEEP
U.start
U.end
U.step
F (Hg)
t.drop
t
U
t
U.step
U.start
t.step
t.meas t.meas
Area (Hg)