Shared ladder program
Ladder logic: 4 rungs with XIC, XIO, OTL
A runnable ladder logic program with 4 rungs using XIC, XIO, OTL, TON, OTU, RES. Open it in the free browser PLC simulator to edit, run and fork it. No install, no account.
What's in this program
- 4 rungs
- Uses parallel branches (OR logic)
Instructions used: XIC (examine-if-closed contact (normally open)), XIO (examine-if-open contact (normally closed)), OTL (output latch coil), TON (on-delay timer), OTU (output unlatch coil), RES (reset a timer or counter), CTU (count-up counter).
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More example programs
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The classic latching start/stop circuit. A momentary start button energises the motor, a parallel branch off the motor output seals the rung in, and a normally-closed stop button drops it out.
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Batch counter with compare
Each part pulse increments a count-up counter; a compare instruction watches the accumulator and fires a Batch Complete output when it reaches the target. Shows CTU plus a CMP against a constant.
Want to build your own? Open the free ladder logic sandbox.