In pneumatics diagrams, a dashed line is used to indicate a control signal path; which is often a pilot line.

In pneumatics diagrams, a dashed line is used to indicate a control signal path; which is often a pilot line.

• A. Pilot line
• B. Electrical line
• C. Emergency line
• D. Vent line

Answer: (A)

Dashed lines in pneumatics diagrams show control signal paths, which are used to operate valves rather than carry the main compressed air. The line that carries this control signal is the pilot line. It’s typically a smaller, separate path whose pressure moves the valve to actuate the main air flow when needed. An electrical line would indicate wiring for electrical control, not a pneumatic control signal. An emergency line refers to safety/switch-off paths, and a vent line is an exhaust path to atmosphere. So the dashed line best represents the pilot line—the control signal that drives the valve.

Dashed lines in pneumatics diagrams show control signal paths, which are used to operate valves rather than carry the main compressed air. The line that carries this control signal is the pilot line. It’s typically a smaller, separate path whose pressure moves the valve to actuate the main air flow when needed. An electrical line would indicate wiring for electrical control, not a pneumatic control signal. An emergency line refers to safety/switch-off paths, and a vent line is an exhaust path to atmosphere. So the dashed line best represents the pilot line—the control signal that drives the valve.