BAS 100B/W Instruction Manual page 105

d) The sample interval is equal to the product of the Scan Rate and the Drop
Time (or Step Period) (e.g., the default value is 6 mV.)
Graphics Menu
Single Graph displays the appropriate current vs. potential plot for all the
techniques.
Analysis Menu
The Auto option for Results Graph displays the current vs. potential plot,
and the peak potential and peak current are listed in the Main window for
ACV/Pand PSACV/P. It is disabled for SHACV/P. Alternative baselines can
be set by the user through the Manual option.
Triangular Wave A.C. Techniques (TACV/P, DTACV/P)
These techniques are similar to the sinusoidal techniques in that the potential
waveform consists of an A.C. waveform superimposed on a slowly varying D.C.
waveform. However, for these techniques, the A.C. waveform is triangular (Figure
10-23). The A.C. current response is therefore more simple, and is shown in Figure
10-23 and Figure 10-24. The charging (capacitive) current approximates to a square
wave, the amplitude of which is proportional to the double-layer capacitance.
Triangular wave A.C. techniques were originally used to measure double-layer
capacitance; more recently, there have also been used in corrosion studies.
A.
E
T.W. AMPLITUDE
PERIOD
QUIET
TIME
Figure 10-23. Potential wave form and current sampling regime for TACV/P.
E ac
APPLIED POTENTIAL
B.
CAPACITIVE CURRENT
FARADAIC CURRENT
SAMPLING TIME
t
10-37
I dc
I dc
t