Dual Output Control 4.8 - Partlow MIC 2000 Installation And Operation Manual

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Dual Output Control 4.8

Dual output control can be performed when two outputs are specified. The outputs may be
programmed for On-Off, Time Proportioning, or Current Proportioning, as applicable.
The output action is dependent upon the setpoint, the process value, and Tune mode parame-
ters. If two proportional outputs are selected, both output proportional bands will be biased so
that 0 % of output is seen when the process value equals setpoint. The output(s) can be
biased by the use of the Tune mode parameters FOP and SPrd as shown below.
FIGURE 4-2
100%
Proportional
Reverse
Output 1
Acting Output
First
Output
Position = X
The first output is programmed as a proportional reverse output and the second as a propor-
tional direct output. (See Glossary, page 63, for definitions of these terms). Dual propor-
tioning outputs are provided with separate proportional band and cycle time adjustments for
each output.
Direct
Acting Output
Control
Setpoint
Spread = Y
+Y
-X
100%
Proportional
Output 2
Process
Value