What is the purpose of reading a schematic in an electrical control system?

• A. To identify the color coding of wires.
• B. To measure system voltage.
• C. To understand wiring, connections, and operation of the control system.
• D. To estimate production output.

Answer: (C)

Understanding how the system is wired and how it operates is what reading a schematic is all about. A schematic uses symbols to show each component, its terminals, and how power and control signals travel from source through switches, relays, sensors, and actuators to produce the desired action. By tracing the lines, you can see which devices energize in response to a given input, how the control logic is implemented, and where a fault might be hiding. This map is essential for installing, testing, diagnosing problems, and making design changes because it translates the real wiring into a readable picture of the system’s function. Color coding of wires and using a meter to measure voltage are useful tasks, but they serve different purposes than interpreting how the entire control circuit works.