The PID variable in the PID instruction is a structure variable. You cannot allocate variables other than PID variables (address format: U_) to operand HP. For the internal structure of the PID variable designated to operand HP, refer to the following table.
PID Variable
|
PID Variable |
Variables Settings |
Description |
|---|---|---|
|
VariableName.Q |
Bit Variable |
Completion Flag for PID Instruction Processing |
|
VariableName.PF |
Bit Variable |
Processing Deadband Range Flag |
|
VariableName.UO |
Bit Variable |
Output Values over the Lower Limit |
|
VariableName.TO |
Bit Variable |
Output Values over the Upper Limit |
|
VariableName.IF |
Bit Variable |
Integral Setting |
|
VariableName.KP |
Integer Variable |
Proportional Constant |
|
VariableName.TR |
Integer Variable |
Integral Calculus Time |
|
VariableName.TD |
Integer Variable |
Differential Calculus Time |
|
VariableName.PA |
Integer Variable |
Processing Deadband Range |
|
VariableName.BA |
Integer Variable |
Bias (Offset) |
|
VariableName.ST |
Integer Variable |
Frequency in Sampling |
Other operands are as follows.
S1: Set Point
S2: Process Variable
S3: Tieback Value (The set value is output when an instruction is disabled)
D1: Control Variable