Which of the following rules applies when drawing a ladder diagram?

When drawing a ladder diagram, the rule that is applicable is that each rung can have more than one output device. This allows for the representation of multiple actions that can occur simultaneously based on the conditions met in the rung. Each rung typically represents a specific control logic path, and having multiple output devices enables a single rung to control various actuators or indicators at the same time.

This flexibility is essential in practical applications, as multiple devices might need to be activated together. For instance, in a motor control application, you could have different indicators or relays that respond based on the same set of input conditions, which can be effectively illustrated in a single rung of the ladder diagram. Such design aids in simplifying both the control logic and the physical circuitry, streamlining troubleshooting and maintenance.

Other options do not reflect the typical practices in ladder diagram design. For instance, limiting each rung to a single input device would be overly restrictive and does not accurately represent practical scenarios where multiple conditions can influence the outputs. Connecting all devices in series is also not a requirement, as parallel connections are commonly used in ladder logic to accommodate various devices acting on the same condition. Additionally, ladder diagrams are conventionally drawn horizontally rather than vertically, which emphasizes the flow of logic in a way