Yamatake SDC35, User Manual

Page: 85 / 280

5-27
The following figure shows the conceptual diagram expressing differences in
control result using the PID constant calculated by each AT type:
• For the AT Proportional band adjustment (At-P), AT Integral time adjustment
(At-I), and AT Derivative time adjustment (At-d), the value that the PID constant
calculated by the AT is multiplied by each coefficient is written into the set value
of the PID constant. However, the coefficient must be a value in the PID
constant setting range.
Note
• In the Heat/Cool control, it is possible to execute the AT only on the heat or
cool side.
• Setting that the AT is activated for only the heat PID constant in the
Heat/Cool control:
50.0% <MV low limit at AT (At.oL) < MV high limit at AT (At.oH)
• Setting that the AT is activated for only the cool PID constant in the
Heat/Cool control:
MV low limit at AT (At.oL) < MV high limit at AT (At.oH) < 50.0%
For details about AT, refer to;
AT stop/start (on page 5-11) and AT function (on page 5-29) .
Chapter 5. DETAILED DESCRIPTION OF EACH FUNCTION
PV
Time
Difference in PV change when SP is changed.
SP
AT type = 1
(Immediate response)
AT type = 0 (Normal)
AT type = 2 (Stability)