Siemens SIMATIC S7-1200 Function Manual page 165

Reaction to error
NOTICE
Your system may be damaged.
If you output "Current value while error is pending " or "Substitute output value while error is
pending" in the event of an error, PID_Temp remains in automatic mode or in manual
mode. This may cause a violation of the process value limits and damage your system.
It is essential to configure how your controlled system reacts in the event of an error to
protect your system from damage.
PID_Temp is preset so that the controller stays active in most cases in the event of an error.
If errors occur frequently in controller mode, this default reaction has a negative effect on the
control response. In this case, check the ErrorBits parameter and eliminate the cause of the
error.
PID_Temp generates a programmable output value in response to an error:
● Zero (inactive)
At all errors, PID_Temp switches to the "Inactive" operating mode and outputs the
following:
– 0.0 as PID output value (PidOutputSum)
– 0.0 as output value for heating (OutputHeat) and output value for cooling (OutputCool)
– 0 as analog output value for heating (OutputHeat_PER) and analog output value for
– FALSE as PWM output value for heating (OutputHeat_PWM) and PWM output value
This is independent of the configured output value limits and the scaling. The controller is
only reactivated by a falling edge at Reset or a rising edge at ModeActivate.
● Current value while error is pending
The error response depends on the error occurring and the operating mode.
If one or more of the following errors occur in automatic mode, PID_Temp stays in
automatic mode:
– 0000001h: The Input parameter is outside the process value limits.
– 0000800h: Sampling time error
– 0040000h: Invalid value at Disturbance parameter.
– 8000000h: Error during the calculation of the PID parameters.
PID control
Function Manual, 03/2017, A5E35300227-AC
cooling (OutputCool_PER)
for cooling (OutputCool_PWM)
Using PID_Temp
6.2 Configuring PID_Temp
165