Honeywell DR4300 Product Manual page 108

DR4300 Circular Chart Recorder
Lower Display
Prompt
CTRALG
(continued)
PWR UP
DEFDSP
96
Upper Display
Range of Setting
or Selection
PID A
NOTE: PID A should not be
used for proportional only
action (that is, no integral
(reset) action). Instead, use
PDMR with "RATE T" set to
0.
PDMR
MAN [factory setting]
AUTO
INP [factory setting]
SP
DR4300 Circular Chart Recorder Product Manual
Parameter
Definition
PROPORTIONAL-INTEGRAL-DERIVATIVE—
PID A is normally used for three-mode control. Unlike
ON/OFF control, with PID A the output can be
somewhere between 100 % and 0 %. PID A applies all
three control actions (Proportional, Integral, and
Derivative) to the error. This control can be tuned using
the parameters in the tuning group.
• Proportional (gain) regulates the controller's output in
proportion to the size of the error (difference between
setpoint and process variable).
• Integral (reset) regulates the controller's output in
proportion to the size of the error and time the error
has existed (duration). The amount of corrective action
depends on the value of the proportional gain.
• Derivative (rate) regulates the controller's output in
proportion to the rate of change of the error. Again, the
amount of correction depends on the gain setting.
PROPORTIONAL-DERIVATIVE with MANUAL
RESET—Use PDMR whenever integral action is not
needed during automatic control. The output is calculated
with no integral contribution. Then the value specified
using the tuning parameter "MANRST" (manual reset) is
added to the computed output to determine the controller
output.
Switching between manual and auto modes will not be
bumpless in PDMR.
PDMR variations: If you select PDMR you can configure
the following variations:
• PD (proportional-derivative) control, by setting
MANRST to 0.
• P (proportional only) control, by setting MANRST
(integral term) to 0 and rate (derivative term) to 0
(tuning parameter "RATE T").
POWER UP CONTROLLER MODE RECALL—This
selection determines which mode the recorder will use
when it restarts after a power loss.
MANUAL—At power-up, the recorder will use manual
mode with the output value displayed.
AUTOMATIC—At power-up, the recorder will return to
the automatic mode.
DEFAULT DISPLAY—This selection determines the
default display (input or active setpoint) on power up.
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