Section 4 Settings Required for Basic Control
4-14
Settings Required
for Basic Control
4.7 Setting output parameters
■ Control period
• The output period (control period) must be set. A shorter control
period improves controllability, however, when a relay is used to
control a heater, a control period of at least 20 seconds is recom-
mended to preserve product life. After setting the control period in
the initial settings, readjust it as necessary using trial runs.
• Set the values in "cp: Control period (heat)" and "c-cp: Control
period (cool)". The default value is "20.0 sec".
• "Control period (cool)" can only be used in heating/cooling control.
• When each channel is used independently for control, set the control
period separately for each channel.
■ Direct operation (cool) / Reverse operation (heat)
• Control that increases the MV as the PV increases is called direct
operation (cool), and control that increases the MV as the PV
decreases is called reverse operation (heat).
• For example, when the present value (PV) is less than the set point
(SP) during heating control, the manipulated valuable (MV) is
increased in proportion to the difference between the PV and SP. As
such, heating control is "reverse operation". Cooling control, which
does the opposite, is "direct operation".
• Set "Direct / reverse operation" to "or-r: Reverse operation" or
"or-d: Direct operation". The initial setting is "Reverse operation
(heat)".
• When each channel is used independently for control, set the direct /
reverse operation separately for each channel.
cp
20.0
l.adj
c-cp
20.0
l.adj
25.0
0.0
0.0
ore
or-r
l.1
Temperature is highTemperature is low
MV
Set value (in general)
100%
0%
Direct action
Temperature is highTemperature is low
MV
Set value (in general)
100%
0%
Reverse action