In a logical diagram, what determines the signals sent to devices in a control diagram?

In a logical diagram, the control signals are used to manage and dictate the operations of devices within a control system, which ultimately involves various control functions and reactions based on input and feedback. Control power plays a crucial role in this context as it provides the necessary energy for the control circuit to function and send the appropriate signals to control devices. Without control power, the logical circuits cannot operate, nor can they send signals, regardless of the control signals themselves.

Control power typically refers to the voltage and current supplied to the control devices, enabling their operational state. It ensures that devices receive the power they need to execute control functions or respond to logical conditions established within the control diagram. In doing so, it directly influences the behavior of the entire system, hence determining which signals are sent and when.

Understanding this, other options such as control signals and the power supply are essential components of a control system but do not solely determine the signals sent to the devices without the presence of control power to facilitate their operation.