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Control Period (Display Level 1)
PV
SV
Control period parameter symbol
Control period of currently selected loop
(Unit: seconds)
•
This sets the control period. It is valid when SW203-1 is OFF (PID control).
•
The control period is the time required to complete one transistor output or volt-
age output ON/OFF cycle.
ON time
Control period
ON
OFF
Hysteresis (Display Level 1)
PV
SV
Hysteresis parameter symbol
Hysteresis of currently selected bank and loop
(Unit: %FS)
•
Hysteresis prevents control output chattering and eliminates noise influences.
•
When switching from ON to OFF, operation proceeds at the set point. When
switching from OFF to ON, operation proceeds at a lower point determined by
the hysteresis SV, as shown in the illustration below.
ON
OFF
Hysteresis
Set point
Hysteresis is applied in the following situations.
•
When ON/OFF control is selected (i.e., when SW203-1 is ON).
•
When advanced PID control is selected (i.e., when SW203-1 is OFF) and P
(proportional band) is 0.
Alarm Hysteresis (Display Level 1)
PV
SV
Alarm hysteresis parameter symbol
Alarm hysteresis of currently selected loop
(Unit: %FS)
•
Alarm hysteresis prevents alarm output chattering and eliminates noise in-
fluences. It is invalid when both ALARM mode 1 and ALARM mode 2 are set to
“0.”
•
When switching from OFF to ON, operation proceeds at the set point. When
switching from ON to OFF, a hysteresis SV operating band is provided which
Parameter Displays and Settings
