User Manual

PID is easy
8.4 PID_3Step instruction
Easy Book
Manual, 03/2014, A5E02486774-AF
179
8.4
PID_3Step instruction
The PID_3Step instruction configures a PID controller with self-tuning capabilities that has
been optimized for motor-controlled valves and actuators.
Table 8- 6 PID_3Step instruction
LAD / FBD
SCL
Description
"PID_3Step_1"(
SetpoInt:=_real_in_,
Input:=_real_in_,
ManualValue:=_real_in_,
Feedback:=_real_in_,
InputPer:=_word_in_,
FeedbackPer:=_word_in_,
Disturbance:=_real_in_,
ManualEnable:=_bool_in_,
ManualUP:=_bool_in_,
ManualDN:=_bool_in_,
ActuatorH:=_bool_in_,
ActuatorL:=_bool_in_,
ErrorAck:=_bool_in_,
Reset:=_bool_in_,
ModeActivate:=_bool_in_,
Mode:=_int_in_,
ScaledInput=>_real_out_,
ScaledFeedback=>_real_out_,
ErrorBits=>_dword_out_,
OutputPer=>_word_out_,
State=>_int_out_,
OutputUP=>_bool_out_,
OutputDN=>_bool_out_,
SetpoIntLimitH=>_bool_out_,
SetpoIntLimitL=>_bool_out_,
InputWarningH=>_bool_out_,
InputWarningL=>_bool_out_,
Error=>_bool_out_,
ErrorBits=>_dword_out_);
PID_3Step configures a PID controller with
self-tuning capabilities that has been
optimized for motor-controlled valves and
actuators. It provides two Boolean outputs.
PID_3Step is a PID T1controller with anti-
windup and weighting of the P- and D-
components.
1
STEP 7 automatically creates the technology object and instance DB when you insert the instruction. The instance DB
contains the parameters of the technology object.
2
In the SCL example, "PID_3Step_1" is the name of the instance DB.