E5CNH E5AN-H E5EN-H Digital Controllers User's Manual - OMRON

Executing Heating/Cooling Control Section 4-4
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When heating/cooling control is selected, the Dead Band and Cooling
Coefficient parameters can be used.
Dead Band For heating/cooling control, the dead band is set with the set point as its
center. The dead band width is the set value of the Dead Band parameter
(adjustment level). Setting a negative value produces an overlapping
band.
Output
Heating
side
0
Set point
If an overlapping band is set, the bumpless function may not operate
when switching between manual operation and automatic operation.
The default is 0.0 EU for a temperature input and 0.00% FS for an analog
input.
Dead band: Dead band
width = A positive value Output
Cooling
side
PV
Heating
side
0
Set point
Overlapping dead band: Dead
band width = A negative value
Cooling
side
Cooling Coefficient 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 proportional
band (P) for the control output assigned to the cooling side. Use this to
achieve balanced control between the heating side and cooling side. The proportional
bands (P) for the control outputs assigned to the heating/cooling
sides can be calculated using the following equations.
P for control output assigned to heating side = P
P for control output assigned to cooling side = P for control output assigned to
heating side × cooling coefficient
The cooling coefficient is multiplied by the P for the control output assigned to
the heating side to obtain control with characteristics that differ from those of
the control output assigned to the heating side.
A cooling coefficient can be set for each PID set. To set the cooling coefficient,
select the PID set number in the Display PID Selection parameter (PID setting
level) and then set the Cooling Coefficient parameter. If the Cooling Coefficient
parameter setting is changed in the adjustment level, the change will be
reflected in the Cooling Coefficient parameter for the current PID set.
Output Output
P for control output
assigned to heating
side × 1.0
P for control output
assigned to heating
side × 1.0
P for control output
assigned to heating side
P for control output
assigned to cooling side
P for control output
assigned to heating side
P for control output
assigned to cooling side
0
Set point
PV
0
PV
P for control output assigned to
P for control output assigned to
heating side × 0.8
heating side × 1.5
PV