Question $4$

$($a$)$ Explain what is Ladder diagram?

$(3$ marks$)$

$($b$)$ List seven basic elements used in Electro pneumatic circuit.

$(7$ marks$)$

$($c$)$ Design two pneumatic circuits and sketch its ladder diagram for direct control of single

acting cylinder in position when cylinder is extended and position when cylinder is

retracted. The designed circuits are solenoid activated and retract when spring return

takes place. Explain the operation of that circuits.

$(10$ marks$)$