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4.7.3
External Control of the Rotation Rate
It is often convenient for the rotation rate to be controlled via an externally
supplied signal. Many potentiostats are capable of providing such a signal to
control the rotation rate while simultaneously performing electrochemical
measurements. An externally supplied signal is also required when performing
hydrodynamically modulated voltammetry, where the rotation rate is varied
sinusoidally as electrochemical measurements are made with the potentiostat.
Figure 4.15: Connecting the Rotation Rate Control Cable
A special cable is available to connect Pine potentiostats to the MSR rotator (see
Figure 4.15). One line of this cable carries an analog rate control signal from the
potentiostat to the INPUT jacks on the front panel of the control box. A second
line carrying a digital control signal is connected to the MOTOR STOP jack on the
back panel of the control box. The other end of the special cable is connected
to the potentiostat.
The analog rate control signal from the potentiostat is a voltage that is
proportional to the desired rotation rate. The MSR rotator is factory configured to
use a 1.0 RPM/mV ratio, which is the ratio compatible with Pine potentiostats.
Other ratios are available for use with other potentiostats (see Section 6.7).
Summary of Contents for MSR 636A
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