eDAQ Picostat, Руководство пользователя

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66 eDAQ Potentiostats
On Windows computers
If you are using a QuadStat, then most constant potential experiments
between ±2.5 V are done by adjusting the internal QuadStat
Applied
Potential, page 57 . If you require applied potentials greater than
±2.5 V, or pulsed waveforms, then you can use the Chart Stimulator
controls as described below.
Chart software can be used to set a constant voltage of up to ±10 V
(which is known as the command voltage) from the
e-corder Output.
This is sent to the Picostat or Potentiostat, or QuadStat, via the ‘E In’
input cable, which then applies this potential across the reference and
working electrodes. The software controls are accessed through the
Stimulator command in the Setup menu,
Figure 5–4 .
To adjust the command voltage you will first need to select the range by
adjusting the Output Range control in the Stimulator controls
Figure
5–5 . The smaller the selected output range, the finer the control that you
will have when you adjust the potential with the Baseline control. To
monitor the current signal at a constant potential:
1. set the Stimulator to Pulse mode;
2. set the Pulse Amplitude to zero volts;
3. set the Baseline control to the desired voltage;
4. adjust the current input range to an appropriate value, page 17
and page 36 ;
5. set the speed of recording (that is the number of data points to be
collected per second) to an appropriate value — you will usually
require at least several hundred data points over the lifetime of your
experiment. The
Chart Software Manual has detailed descriptions
on setting the recording speed; and finally
6. begin the experiment by clicking the Start button in the main
Chart window.
The Stimulator command can be used to alter the applied potential with
a precision better than 1 ms. Pulses up to 30 s long may be created by
this method. For further details on using the Stimulator in Chart refer to
the
Chart Software Manual . An example using the Chart Stimulator is
shown in Figure 5–6 . Note that the pulse amplitudes are added to any
value set by the Baseline control.