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c)
Enter a small duty cycle into the controller’s display – 5% is a good starting point.
d)
In the Gamry Framework, issue the command
Experiment, Named Script, TDC4 Manual Tune
.exp
A display of temperature versus time will be seen.
e)
Examine the temperature trend for a few minutes and guess at the final temperature.
f)
Adjust the duty cycle so the final temperature is about 5 to 15
°
C over ambient temperature.
g)
Wait for the system to settle to a constant temperature. This can take several hours.
3)
Data Acquisition for Tuning
a)
The TDC4 should be in SELF mode and the temperature must be stable. If the
TDC4 Manual
Tune.exp
script is still running, terminate it using the
F2-Skip
button.
b)
Restart the TDC4 Manual Tune .exp Framework script.
c)
Record a few hundred seconds of base line data
d)
Enter a duty cycle that is about 1.5 times higher than current duty cycle. For example, if the
previous power level was 6% increase it to 9%. Note the size of the increase, it will be needed in
later calculations.
e)
Note the time at which the duty cycle increase occurred.
f)
Allow the
TDC4 Manual Tune
script to acquire at least one hour of data. The temperature
versus time curve should start out linear, then begin to curve. See Figure 3-5. This Figure was
generated using a Flex Cell heated with a 200 W heating jacket, with slow stirring. The jump in %
output was from 6% to 10%.
As you can see in this figure, the temperature resolution of the measurement is fairly poor so the
temperature versus time curve can consist of just a few levels.
Figure 3-5
Typical Real Time Plot from TDCTUNE.EXP
Summary of Contents for TDC4
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