What characterizes an Automatic Signal in train operations?

An Automatic Signal in train operations is characterized by being controlled by the movement of trains. This means that the signals are designed to change automatically based on the position and speed of approaching trains. This system enhances operational efficiency and safety by providing real-time updates to train crews, allowing for smoother traffic flow without the need for constant manual input.

While manual operation of signals is a feature of other types of signals, and train schedules are communicated through different means, Automatic Signals specifically serve the purpose of conveying immediate information based on train movements. Similarly, the functionality of these signals is not limited to daylight hours; they are operational at all times, depending on the system in place. Thus, the characteristic of being controlled by the movement of trains distinguishes Automatic Signals from other types of signal systems.