Allen-Bradley · Logix 5000 Controllers
This fault indicates that the Process Variable (PV) health is bad. This can be due to an invalid input value, communication issues, poor signal quality, or the PV exceeding its Engineering Unit (EU) limits. In the PPID instruction, the equivalent Sts_PVBad status is set under these conditions, plus additional internal conditions not present in PIDE.
Click steps to track your progress.
Verify the raw PV input value at its source (e.g., analog input module terminals) using a multimeter or process calibrator
Check the communication status of the PV input module in the I/O tree, looking for I/O module faults
Examine the configured EU limits for the PV (PVEUMin, PVEUMax or Cfg_PVEUMin, Cfg_PVEUMax) to ensure they are appropriate for the process range
Confirm that Inp_PVBad (for PPID) is not manually set or being driven by external logic