The TTC's Signal System, Explained | cityscape | Torontoist
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The TTC’s Signal System, Explained

New video outlines how signal systems work, and why scheduled subway closures are actually good and useful things.

Unless you happen to be a subway operator with the Virtual TTC Academy, you might not be entirely clear on how the transit system’s signal system works—or even what, precisely, it’s for. You might, in fact, be familiar with it mostly thanks to the kind of announcement featured at the beginning of the video above: “Attention customers on Line 1, Yonge-University-Spadina: due to signal problems at Davisville Station, expect longer-than-normal travel times during your commute.” (We’re almost positive “Line 1” will soon start sounding far less strange.)

The current fixed-block signal system is, although safe, also old and outmoded: the TTC is in the process of replacing it with a new Automatic Train Control system. The video serves as an introduction to these two systems and the differences between them, but it clearly has an ulterior motive—to, by educating customers about technical and logistical challenges, help them understand why it really is necessary to schedule occasional weekend subway closures. And after learning that workers can accomplish as much during a localized one-day shutdown as they would during five whole weeks of overnight construction, it’s possible patrons will indeed be more sympathetic.