Engineering

Please draw a Sequential Step Chart (SSC) for the following PLC sequential control problem.

6-11(a) Write a documented program that will implement the following continuous filling operation:

Start the conveyor when the Start button is momentarily pressed.

Stop the conveyor when the Stop button is momentarily pressed.

Energize the Run status light when the process is operating.

Energize the Standby status light when the process is stopped.

Stop the conveyor and energize the Standby light when the right edge of the box is first sensed by the photosensor.

With the box in position and the conveyor stopped, open the solenoid valve and allow the box to fill. Filling should stop when the Level sensor goes true.

Energize the Full light when box is full. The Full light should remain energized until the box is moved clear of the photosensor.

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Use the Silo Simulator screen and the following addresses to simulate the program:

Start (NO contact) _ I:1/0

Stop (NC contact) _ I:1/1

Photo Switch (NO contact) _ I:1/3

Level Switch (NO contact) _ I:1/4

Conveyor Motor _ O:2/0

Solenoid _ O:2/1

Run Light _ O:2/2

Standby Light _ O:2/3

Full Light _ O:2/4