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Hello can someone tell me please if in theory the following would work with the info provided and if not can you please let me know why and maybe what I could do to correct the problem. (for izumi plc)

thanks in advance
                              Rob

LOD 11
OR 202
AND CNTO
OUT 202
LOD 202
OUT 202
LOD CNT 0
LOD 6
OUT CNT 0
5

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Design a ladder diagram and ketstroke sequence for an air cylinder which has the following programme requirments.

Use cylinder B (output 202) on the test rig which is a spring return cylinder. Cylinder B is the middle clyinder on the test rig.

Cylinder B has two N/O limit switches (limit 3 & 4) one at each end of the piston travel.

Pushing the start button (input 11) on the test rig will start the programme.

The stop button (input 10) will stop the process at any point in the programme. The programme must completely reset. (Counters, timers, internal realys and outputs must revert to low state)

Limit switch 3 must be closed before cylinder B will extend. If cylinder B is extended/pushing of the start button will cause nothing to happen in the programme.
(Counters, timers, internal realys and outputs must remain LOW)

After the start button is pressed, cylinder B will extend fully, operating input 4, hold for two seconds, then retract fully operating input 3. NOTE: the two second delay does not include cylinder piston travel.

The cylinder will automaticlly extend and retract another four times (five cycles in total)

After five extend/retract cycles the programme must completely stop (Counters, timers, internal realys and outputs must revert to low state)

A new sequence can be commenced by pressing the start button again.

If the programme is terinated early by pressing the stop button, the programme must completely reset.
(Counters, timers, internal realys and outputs must revert to low state)
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