Omron E5CN-HT User Manual page 239

Adjustment Level
Setting
See
See
c-sc
Cooling Coefficient
Function
Setting
See
See
D action: Refers to a control action that is proportional to the time derivative of
the control error. The proportional control and integral control cor-
rect for errors in the control result, and thus the control system is
late in responding to sudden changes in temperature. The derivative
action increases the MV in proportion to the slope of the change in
the temperature as a corrective action.
• The set values are saved in the Proportional Band, Integral Time, and
Derivative Time parameters for the selected PID set.
Parameter
name
Proportional
Band
Integral Time
Derivative Time
■ Related Parameters
AT execute/cancel (adjustment level): Page 208
PID * proportional band, PID * Integral time, PID * Derivative time (PID setting
level): Page 227
If the heating characteristics and cooling characteristics of the control object
are very different and good control characteristics cannot be achieved with the
same PID constants, the cooling coefficient can be used to adjust the propor-
tional band (P) for the control output assigned to the cooling side.
• In heating/cooling control, the proportional band P for the cooling control
output is calculated using the following formula to set the cooling coeffi-
cient:
Cooling control output side P = Cooling coefficient
• When the Automatic Cooling Coefficient Adjustment parameter is set to
ON, the cooling coefficient is set automatically when AT is executed. If
there is strong non-linear gain for the cooling characteristics, however, it
may not be possible to obtain the optimum cooling coefficient at the Con-
troller.
• The set value is saved in the Cooling Coefficient parameter for the current
PID set.
Setting range
0.01 to 99.99 None
■ Related Parameters
Proportional band (adjustment level): Page 216
Models
Controllers with Temperature
Inputs: 0.1 to 3,240.0
Analog input: 0.1 to 999.9
Standard, heating/cooling, or posi-
tion-proportional (close) control:
0.0 to 3,240.0
Position-proportional (floating)
control: 0.1 to 3,240.0
0.0 to 3240.0
The control must be heating/cooling
control and 2-PID control.
Unit Default
1.00
Section 5-5
Unit Default
C or F 8.0
%FS 10.0
Second 233.0
Second 40.0
P (proportional band)
217