What is the Automatic Block Signal System (ABS)?

The Automatic Block Signal System (ABS) is designed to enhance safety and efficiency in rail operations by utilizing automatic signals. This system operates by providing signals that automatically change based on the presence or absence of trains within certain blocks of the track. The primary function of ABS is to prevent collisions by ensuring that trains are separated by safe distances, which is facilitated by the automatic aspect of the signals.

In this system, signals are activated and controlled automatically according to the train's movements, allowing for continuous monitoring and adjustments without the need for manual intervention. This significantly reduces the risk of human error and enhances the overall reliability of train operations. The ability to use both automatic and potentially manual signals under certain conditions is what characterizes this system, distinguishing it from systems that rely solely on manual signals or do not incorporate any form of signal controls.

This emphasis on automation, while still having the capability to incorporate manual signals, aligns with the definition of ABS as an advanced signaling system that optimizes safety and operational efficiency.