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[PID zone function]
When PID zone function “Used” is selected, and if SV (or Step SV for the program
control) is lower than PID zone value, the control is performed with PID zone
parameters of the relevant PID zone value.
If the next PID zone value is lower than the current one, the next PID zone parameters
will not be effective.
During program control, the currently performing step SV is applicable to the PID zone.
In the case of (Fig. 7.3.9-1), “SV: 150 ” is higher than “PID zone value 1: 100 ”, and
lower than “PID zone value 2: 200 ”, so control is performed using PID zone
parameters of PID zone value 2.
As PID zone value 4 has not been set, even in the case SV is higher than PID zone
value 3, control is performed using PID zone parameters of PID zone value 3.
(Fig. 7.3.9-1)
PID zone value 3: 300
PID zone value 1: 100
PID zone value 2: 200
SV: 250
SV: 150
SV change
Controls using PID zone
parameters of PID zone
value 2.
Controls using PID zone
parameters of PID zone
value 3.
Controls using PID zone
parameters of PID zone value 1.
Controls using PID zone
parameters of PID zone value 2.
Controls using PID zone
parameters of PID zone value 3.
If PID zone value 4 has not been set, for the zone which is
higher than the PID zone value 3, control is performed using
parameters of PID zone value 3.