eDAQ Picostat, Руководство пользователя

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Chapter 5 — Techniques 69
To adjust the potential you will first need to select the range by
choosing the Output Voltage command in the Setup menu to activate
the Stimulator Constant Output dialog box,
Figure 5–8 . The smaller the
selected output range, the finer the control that you will have when you
adjust the potential.
The Timed Events (Setup menu) feature and macros can be used to keep
the potential constant for a fixed period of time, or to drive the reaction
backwards by applying an opposite potential to perform an
oxidation/reduction cycle.
The Chart software Stimulator command (in the Setup menu) can also
be used to set up pulses, stepped pulses, and staircase ramp
waveforms for the Potentiostat or Picostat. See the
Chart Software
Manual for more details.
You can also use the Timed Events feature (Setup menu) to adjust the
current at predetermined time intervals after the start of recording. For
example, the settings shown in
Figure 5–9 will maintain a potential of
1.25 V for 30 minutes after which the potential will be decreased to
0.50 V in order to reverse the reaction, resulting in a Double Step
Chronoamperometric experiment. Any number of steps at any potential
could be set up with this feature. However, Timed Events can be slightly
delayed (by up to 0.1 s) depending on the model of computer and
what else is happening in the computer operating system. For accurate
timing it is better to use the Chart Stimulator which is fully under the
control of the internal
e-corder clock.
Changing the potential
after a period of 30 s Access Timed Events
from the Setup menu
Figure 5–9
Adjusting potential with
the Chart Timed Events
feature. (Macintosh only)