Allen-Bradley · Logix and SLC PLC
This fault occurs when the target processor is undergoing a program download, making it temporarily inaccessible for other operations or communications. During a download, the processor's resources are dedicated to the update, preventing external access.
Click steps to track your progress.
Verify if an authorized program download operation is currently active or recently initiated from any connected programming workstation or HMI.
Inspect the PLC processor's status indicator LEDs (e.g., RUN, FAULT, COMM, PROG) for patterns consistent with a program download or busy state.
Attempt to establish communication with the PLC using the appropriate programming software (e.g., Studio 5000 Logix Designer or RSLogix 500) to determine the exact processor mode and download progress.
Check for any communication disruptions or network issues that might be prolonging or interrupting a download process, leading to a 'not accessible' state.