What does the abbreviation YL-S stand for in railroad signaling terminology?

What does the abbreviation YL-S stand for in railroad signaling terminology?

• A. Main Track Yard Limits Signaled
• B. Track Warrant Control
• C. Current of Traffic
• D. Traffic Control

Answer: (A)

YL-S denotes Yard Limits that are controlled by signals, specifically on the main track. Yard Limits define a portion of track where movements are restricted to protect yard operations, and the signaled designation means those movements are governed by signal indications rather than other authorization methods. The “Main Track” part clarifies that these signaled limits apply to the mainline section through the yard area, not just yard tracks. So the expansion is essentially Main Track Yard Limits Signaled. It’s not Track Warrant Control, Current of Traffic, or Traffic Control, which are different dispatching concepts.

YL-S denotes Yard Limits that are controlled by signals, specifically on the main track. Yard Limits define a portion of track where movements are restricted to protect yard operations, and the signaled designation means those movements are governed by signal indications rather than other authorization methods. The “Main Track” part clarifies that these signaled limits apply to the mainline section through the yard area, not just yard tracks. So the expansion is essentially Main Track Yard Limits Signaled. It’s not Track Warrant Control, Current of Traffic, or Traffic Control, which are different dispatching concepts.