LD Editor — Ladder Diagram

LD Editor — Ladder Diagram

The Ladder Diagram editor in KVPAC IDE brings the familiar rung-and-rail model to a modern web interface. Program relay logic the way electricians and control engineers read it.

Editor Capabilities

  • Contacts and coils — normally open/closed contacts, output, set/reset, and comparison coils from the palette
  • Power rails and rungs — left/right rails with unlimited rungs; drag to reorder
  • Function block calls — place any function block (timers, counters, math, or your own) directly on a rung
  • Live wiring validation — open branches and unconnected elements are flagged before compile
  • Cross-reference — click any variable to jump to its declaration and every usage

AI/MCP Assistance in LD

  • Describe the interlock in plain English — KVPAC generates the rung logic
  • Ask for an explanation of an inherited rung and get a line-by-line reading
  • Request refactoring of duplicated rung patterns into reusable function blocks

Simulation and Debugging

  • Force and toggle inputs; watch contact states change during simulation
  • Power-flow highlighting shows energised paths in real time
  • Breakpoints on rungs with single-step execution

Who Uses LD

Machine builders and maintenance teams working with motor starters, interlocks, safety chains, and sequential relay-replacement logic.


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