Selecting The Control Method - Omron E5EK PROGRAMMABLE TYPE User Manual

CHAPTER 4 APPLIED OPERATION

4.1 Selecting the Control Method

J Heating and
cooling control
F Dead band
Output
Heating
side
0
Set point
F Cooling
coefficient
4--2
When selecting the control method, set the parameters according to the
following table. (Parameters are factory-set to heating control.)
Parameter
Control Output 1
Control
Method
Heating control
Control output (heat)
(Standard)
Cooling control
Control output (heat)
(Standard)
Heating and cooling
Control output (heat)
control
(Parameters are factory-set to heating control.)
• For details on how to assign outputs, see 3.3 Setting Output Specifica-
tions (page 3-7).
• When heating and cooling control is selected, the "dead band" and
"cooling coefficient" parameters can be used.
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 (level 1 mode). Set-
ting a positive value produces a dead band, while setting a negative val-
ue produces an overlap band.
The dead band is factory-set to "0.00:0.00%FS."
Dead band: dead
band width = positive
Cooling
side
PV
If the heating and cooling characteristics of the control target greatly
differ, preventing satisfactory control characteristics from being ob-
tained by the same PID parameters, adjust the proportional band (P at
cooling side) using the cooling coefficient to balance control between
the heating and cooling sides. In heating and cooling control, P at the
heating or cooling side is calculated by the following formula:
Heating side P = P; Cooling side P = cooling coefficient ¢ P
Control Output 2
Assignment Assignment
-
-
Control output (cool)
Output
Heating
side
0
Set point
Direct/Reverse
operations
Reverse operation
Direct operation
Reverse operation
Overlap band: dead
band width = negative
Cooling
side
PV