Special Unit Layout Error (I/O Points/Module Count Exceeded)

What does 2124 mean?

This error indicates an incorrect layout or excessive configuration of special units (modules) on the base unit. It occurs when the number of connectable modules exceeds 10, when a module causes total I/O points to exceed 4096 (for L26CPU-BT) or 1024 (for L02CPU), or if a module is installed across an I/O point boundary. This fault results in the CPU stopping operation.

• The total number of connectable modules on the base unit has exceeded the limit of 10 modules.
• An installed module causes the total I/O points to exceed 4096 (L26CPU-BT) or 1024 (L02CPU).
• A module is installed in a position that causes its I/O points to cross the 4096 or 1024 I/O point boundary.
• Potential hardware failure of the CPU module, I/O module, intelligent function module, or END cover if the error persists after corrective actions.

Click steps to track your progress.

1. 1

   Reduce the number of connectable modules to 10 or less.

2. 2

   Remove any module that causes the system's total I/O points to exceed 4096 (for L26CPU-BT) or 1024 (for L02CPU).

3. 3

   Replace the module installed at the end of the base unit with one whose occupied I/O points do not exceed the limit of 4096 or 1024 points.

4. 4

   Reset the CPU module and attempt to transition it to RUN mode.