7FFF hex
Internal FB Error
ABB · AC500 Function Block Libraries
What does 7FFF hex mean?
This diagnostic code (represented by value 16#7FFF) indicates a severe internal error within a PLCopen Safety function block. This implies a malfunction in the block's internal logic or execution, preventing it from performing its intended safety function correctly and potentially leading to a safe state.
Source: ABB AC500 Function Block Libraries
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