YOKOGAWA NEW GREEN SERIES, User Manual

Page: 54 / 98

3-12
<Toc> <3. Operations>
IM 05D01C12-41E 4th Edition: May 31, 2006-00
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Controller Behavior and Control Output Manipulation when the Dead Band
is Negative
The following is an example when the DB parameter is set at -12.4%.
If you hold down the key with the heating-side output under manipulation (i.e., cooling-
side output C = 0.0%), the heating-side output (H =) decreases. If the output H falls below
24.8%, the cooling-side output C begins to increase from 0.0%. If you keep the
key
held down longer and the output C rises above 24.8%, the output H goes to 0.0% and you
enter the state of manipulating the cooling-side output.
Cooling-side
manipulated output
Heating-side
manipulated output
Output (%)
24.8
DB=-12.4
12.4 0 -12.4
Change in manipulated output when the dead band is negative
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Manipulating the Control Output during Position Proportional Control
The controller continues to provide control output as long as the or key is being
pressed.
key: Closes the valve.
key: Opens the valve.
SET/ENT
A/M
PV
AL1 2 3 4
MAN
REM
OUT display
MAN lamp
ON.
Displays the
valve opening
(0 to 100%).
Note : The output high limit (OH) and output low limit (OL) do not restrict the manual output
of position proportional control.
3.10 Switching between Remote (REM) and Local
(LCL)
The following operating procedure describes an example of switching from Local (LCL) to
Remote (REM).
Switching between REM and LCL is possible for only controllers with remote input feature.