Which statement is not true of a ladder diagram?

• A. It can have more than one output device on each rung
• B. It uses wires and rungs
• C. It is read left to right
• D. It shows power distribution on a device

Answer: (A)

The main idea here is how ladder diagrams encode control logic. Each rung is a self-contained path: when the conditions on the left are met, the output coil on the right is energized. The diagram uses wires (rails) and rungs, and the logic on a rung is read from left to right, with power coming in on the left and the controlled device on the right.

A rung is designed to drive a single output coil. Although you can place multiple inputs in various configurations to control that condition, you don’t place more than one output device on the same rung. If you need multiple devices to respond to the same condition, you’d typically replicate the rung for each output or use a relay/coil that then drives the several devices through its own contacts.

That’s why the statement about having more than one output device on each rung isn’t true, while the other statements correctly describe standard ladder-diagram structure and behavior.