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Help me find solution for this logic

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Member level 2
Mar 11, 2006
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plz help

hello guys
plz plz help me in solving this logic

''A PLC program is required to control for a portion of a lumber processing operation in a furniture factory. This system controls four motors that run a conveyor, its lubrication pump and two saws.
Switch S1 controls lubrication pump (o/p M1), S2 controls conveyor motor (o/p M2), S3 controls band saw motor (o/p M3), S4 controls the cross cut saw motor. Following are the conditions for operation,
1. M1 must be on when M2 is on.
2. M3 and M4 must not operate at same time.
3. M1 must be off when M3 or M4 is on.
4 .For conditions 2, 3 systems must get shut down.

A machine is being designed to wrap boxes of chocolate. The boxes arrive at the machine on a conveyor belt. The list below shows the process steps in sequence.
1. The box arrives and is detected by an optical sensor (P), after this the conveyor is stopped (C) and the box is clamped in place (H).
2. A wrapping mechanism (W) is turned on for 2 seconds.
3. A sticker cylinder (S) is turned on for 1 second to put consumer labeling on the box.
4. The clamp (H) is turned off and the conveyor (C) is turned on.
5. After the box leaves the system returns to an idle state.
For the above process develop PLC program In LAD.

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