User Manual

PID is easy
8.4 PID_3Step instruction
Easy Book
Manual, 03/2014, A5E02486774-AF
181
Parameter and type
Data type
Description
ManualUP IN Bool
• Manual_UP = TRUE:
– The valve is opened even if you use Output_PER or a position
feedback. The valve is no longer moved if the high end stop has
been reached.
– See also Config.VirtualActuatorLimit
• Manual_UP = FALSE:
– If you use Output_PER or a position feedback, the valve is
moved to ManualValue. Otherwise, the valve is no longer
moved.
Note: If Manual_UP and Manual_DN are set to TRUE simultaneously,
the valve is not moved.
ManualDN IN Bool
• Manual_DN = TRUE:
– The valve is opened even if you use Output_PER or a position
feedback. The valve is no longer moved if the high end stop has
been reached.
– See also Config.VirtualActuatorLimit
• Manual_DN = FALSE:
– If you use Output_PER or a position feedback, the valve is
moved to ManualValue. Otherwise, the valve is no longer
moved.
ErrorAck
IN
Bool
Resets the ErrorBits and warning outputs. FALSE to TRUE edge
Reset IN Bool Restarts the controller. (Default value: FALSE):
• FALSE to TRUE edge:
– Switches to "inactive" mode
– Resets the ErrorBits and warning outputs
– Clears Integral action
– Maintains PID parameters
• As long as Reset = TRUE, PID_3Step remains in "Inactive" mode
(State = 0).
• TRUE to FALSE edge:
– PID_3Step switches to the operating mode that is saved in the
Mode parameter.
ModeActivate IN Bool The PID_3Step switches to the mode that is saved in the Mode
parameter. FALSE to TRUE edge:
Mode IN Int The desired PID mode; Activated on the leading edge of the Mode
Activate input.
ScaledInput
OUT
Real
Scaled process value
ScaledFeedback OUT Real Scaled valve position feedback
Note: For an actuator without position feedback, the position of the
actuator indicated by ScaledFeedback is very imprecise.
ScaledFeedback can only be used for rough estimation of the current
position in this case.
Output_UP OUT Bool Digital output value for opening the valve. (Default value: FALSE)
If Config.OutputPerOn = FALSE, the parameter Output_UP is used.