SFC Editor — Sequential Function Chart

SFC Editor — Sequential Function Chart

The Sequential Function Chart editor structures a machine or process as steps, transitions, and actions. Each step holds actions; each transition holds the condition that moves the sequence forward.

Editor Capabilities

  • Steps and transitions — place steps, link them with transition conditions, and attach actions per step
  • Branching — parallel (AND) branches with simultaneous activation, and alternative (OR) branches for choice paths
  • Action qualifiers — N (non-stored), S/R (set/reset), P (pulse), D (delayed) and more, per IEC 61131-3
  • Step actions in any language — write step bodies in ST, LD, or FBD; SFC is the shell, not a constraint
  • Deadlock detection — the editor flags unreachable steps and missing transition conditions

AI/MCP Assistance in SFC

  • Describe the sequence in plain language — KVPAC drafts the step/transition chart
  • Explain an inherited chart step by step, including qualifier behaviour
  • Propose guard conditions for transitions from the process description

Simulation and Debugging

  • Watch active steps highlight as the sequence progresses in simulation
  • Force transitions to jump between steps during testing
  • Per-step action inspection with variable watch

Who Uses SFC

Batch and packaging engineers, and anyone whose machine behaviour is best described as an ordered sequence with clear state boundaries.


SFC vs other languages → · Download →