Shared ladder program

Ladder logic: 3 rungs with XIC, falling-edge, CTU

A runnable ladder logic program with 3 rungs using XIC, falling-edge, CTU, OTL, OTU, RES. Open it in the free browser PLC simulator to edit, run and fork it. No install, no account.

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RUNG 1Sensor_A_InputNSensor_A_FallEdgeCTU Sensor_A_DropCountPRE 32767RUNG 2Sensor_A_FallEdgeLSensor_A_DropLatchRUNG 3Sensor_A_DropLatchHMI_ResetDropLogUSensor_A_DropLatchRESSensor_A_DropCount
Static preview of the shared program. The live editor is below.

What's in this program

XICfalling-edgeCTUOTLOTURES
  • 3 rungs
  • Uses parallel branches (OR logic)

Instructions used: XIC (examine-if-closed contact (normally open)), falling-edge (one-shot falling-edge contact), CTU (count-up counter), OTL (output latch coil), OTU (output unlatch coil), RES (reset a timer or counter).

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Want to build your own? Open the free ladder logic sandbox.