Metrohm 746 VA Trace Analyzer - Manual (Page 375)

5.7 Program instructions
746 VA Trace Analyzer / 747 VA Stand
5-224
The current measurement with the DCTMODE measurement mode
normally provides wave-shaped curves which can be evaluated using
the tangent method (baseline of type
linear ) (see section 5.6.3).
U.wave
I.wave
I
U
If peak-shaped curves appear with the DCTMODE mode, these can be
evaluated only if the voltage sweep SSWEEP is used. The evaluation is
then the same as with other peaks using the baselines of type linear ,
polynom or expon. (see section 5.6.3).
I
U U.peak
I.peak
Comments • The DCTMODE measurement mode can be used with all types of
electrodes together with the instructions MEAS , SWEEP , DSWEEP ,
FSWEEP or TSWEEP .
• The electrode type DME , SMDE , HMDE or RDE must be entered before
the DCTMODE measurement mode.
• With the DCTMODE measurement mode, the potentiostat always
operates in the operating mode "fast". SWEEP and FSWEEP are thus
identical for this mode.
• The quantity t.drop important for the definition of t.step depends
on the type of electrode selected:
DME t.drop = 20 ms
HMDE and RDE t.drop = 0 ms
SMDE t.drop = Drop.size ×× 40 ms
see also SWEEP, SSWEEP, DME, HMDE, SMDE, RDE