Manual

5-11
■ Control method
A desired control method can be selected from three kinds of control methods.
• When the control output type is relay (R0), the initial value becomes "0". The
initial value is "1" in other cases.
• "Fixed" of [1: Fixed PID] means that the PID constant is not changed
automatically since the ST is not run. However, the AT can be run even in the
fixed PID control.
• When using the Heat/Cool control (C26=1) or when using the Just-FiTTER
control (JF.ov > 0), the ST is not run even though [2: ST] is set.
• The following Table shows valid and invalid functions related to [1: Fixed PID]
and [2: ST], as well as other related parameters:
Chapter 5. DETAILED DESCRIPTION OF EACH FUNCTION
Item (Setting display/bank) Display Contents Initial value User level
Control method
(Parameter
setting/Parameter bank)
0: ON/OFF control
1: Fixed PID
2: ST (Self-tuning)
0 or 1
Simple,
Standard,
High function
Classification of
Classification Classification of RationaLOOP AT ST Just-FiTTER
Heat/Cool control of RationaLOOP control action function
Normal control Normal PID P control X ❍✽ XX
PI control X ❍✽ X ❍
PD control X ❍✽ XX
PID control X ❍❍❍
RationaLOOP P control X ❍✽ XX
PI control X ❍✽ X ❍
PD control X ❍✽ XX
PID control ❍❍❍❍
Heat/Cool control Normal PID P control X ❍✽ XX
PI control X ❍✽ X ❍
PD control X ❍✽ XX
PID control X ❍ X ❍
RationaLOOP P control X ❍✽ XX
PI control X ❍✽ X ❍
PD control X ❍✽ XX
PID control ❍❍X ❍
Remarks ✽
Adjustment result be-
comes the PID control.
Related settings Control algorithm AT type ST step execution Just-FiTTER overshoot limit/
resolution width restraint/control coefficient
MV low limit at AT ST step settling Just-FiTTER
width settling band
MV high limit at AT ST hunching
settling width
AT Proportional ST step ramp
band adjust change
AT Integral time
adjust
AT Derivative time
adjust