Siemens SIMATIC S7-1200 - Page 175

PID is easy
8.2 PID_Compact instruction
Easy Book
Manual, 03/2014, A5E02486774-AF
175
Parameter and type
Data type
Description
InputWarning_L OUT Bool If InputWarning_L = TRUE, the process value has reached or fallen
below the warning low limit. (Default value: FALSE)
State OUT Int Current operating mode of the PID controller. (Default value: 0)
You can change the operating mode using the Mode input parameter
and a rising edge at ModeActivate:
• State = 0: Inactive
• State = 1: Pre-tuning
• State = 2: Manual fine tuning
• State = 3: Automatic mode
• State = 4: Manual mode
• State = 5: Substitute output value with error monitoring
Error OUT Bool If Error = TRUE, at least one error message is pending in this cycle.
(Default value: FALSE)
Note: The Error parameter in V1.x PID was the ErrorBits field that
contained the error codes. It is now a Boolean flag indicating that an
error has occurred.
ErrorBits OUT DWord The PID_Compact instruction ErrorBits parameters table (Page 177)
defines the error messages that are pending. (Default value:
DW#16#0000 (no error)). ErrorBits is retentive and is reset upon a
rising edge at Reset or ErrorAck.
Note: In V1.x, the ErrorBits parameter was defined as the Error
parameter and did not exist.
1
You can use the outputs of the Output, Output_PER, and Output_PWM parameters in parallel.