Industrial Engineer · phase 3 of 16
Function Block
Reusable program unit with defined inputs, outputs, and retained internal state when instantiated.
The Explain card
- Plain English
- A function block is a reusable piece of logic that keeps its own memory. You make an instance of it, give it inputs, and it remembers its state from one scan to the next.
- Example
- A timer is a function block. Every TON instance keeps its own accumulated time, so twenty conveyors can share one timer design and twenty separate counts.
- Why it matters
- A block written once for one motor, tested and locked, runs identically on every motor in the plant. Fix a bug in the block and every instance gets the fix, which is how large projects stay maintainable.
- Hook
- A function with a memory of its own.
Where it sits in the deck
Phase 3: PLC Program Organization and Execution
How the logic is arranged and how the scan actually runs it, which is the difference between code that works and code that works every time.
