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GRAFCET / SFC

IEC 60848 GRAFCET and IEC 61131-3 sequential function charts: numbered steps with their actions, transitions with their receptivities, and the divergences and convergences — both alternative (OR) and simultaneous (AND) — drawn with the correct single and double bars. Initial steps get their double border, and the engine checks the well-formedness rule every hand-drawn SFC violates: steps and transitions must strictly alternate.

Templates
10
Source language
plaintext
Workstation
Studio
Engine id
grafcet

In the same space

Most users come to GRAFCET / SFC from CODESYS SFC editors, Visio GRAFCET stencils or Hand-drawn sequence charts. flowss runs this engine in the browser — no install, shareable via URL, exportable to PNG / SVG / PDF / source.

Sample templates

All 10
operations
GRAFCET — Rotary Bottling Filler

An eight-step filler cycle from bottle index through nitrogen purge, fill and capping, resolving the question every filler argues about — what happens to a bottle whose cap torque fails — with an alternative divergence that routes it to the rework lane and returns both paths to the idle step.

risk
GRAFCET — Lift Car Door Interlock

The safety sequence a lift door cannot be certified without: dwell, close, and the alternative divergence on the closing step that sends a photo-eye or door-edge trip to a re-open step and back to the dwell timer, so the interlock is only made when the closed limit and the lock both prove.

lean
GRAFCET — CNC Automatic Tool Change

The changeover every SMED study starts with, drawn honestly: a simultaneous divergence runs the swing arm and the magazine index at the same time and a convergence of the same width holds the drawbar until both prove, which is exactly the internal time a single-threaded chart hides.

flow
GRAFCET — Batch Reactor Heat-Hold-Cool

A charge-heat-hold-cool-discharge batch that carries both branch shapes at once: a simultaneous divergence brings the jacket to temperature while the agitator ramps to shear speed, one convergence releases the hold, and an alternative divergence on the assay sends a failed batch round a rework hold rather than out of the vessel.

operations
GRAFCET — Car Park Entry Barrier

Ticket or season card, then raise, hold and lower: two alternative divergences and the alternative convergence between them resolve the barrier's two real arguments — which credential opened it, and what stops it descending onto a vehicle still standing on the safety loop.

operations
GRAFCET — Robot Pick-and-Place Cell

A vision-gated SCARA cell that carries both bars in one chart: the inspection step diverges alternatively on the vision verdict, and the pass branch opens a simultaneous divergence so the arm picks while the tray indexes, closed by a convergence of the same width that will not release the place until both prove.

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