Figure 3 shows a PLC ladder diagram. Write its equivalent instruction list program.

Here are the answers to the questions:

b) The equivalent instruction list program for the given PLC ladder diagram is:

LD NOT C
AND D
OR B
AND A
OUT Y

The boolean expression for the output Y is: $Y = A \cdot (B + (\overline{C} \cdot D))$

a) A PLC pulse timer (TP) is used to generate an output pulse of a fixed duration (preset time, PT) when its input transitions from OFF to ON. The output turns ON immediately upon the input's rising edge and remains ON for the preset time, regardless of whether the input stays ON or turns OFF during that period. If the input turns ON again before the timer completes its cycle, the timer typically resets and restarts its