January 23, 2012

Hot Switches

One of the readers who asked a question through our new segment, “Ask VIA” wondered about how the dropping temperatures in winter affected the tracks… as a little add-on to that question, we offer some more insight into tracks and winter. Not only are the rails affected by the cold, but so are the switches. Transforming VIA will answer the question: how are the switches kept from freezing-up in winter?

Switches can be found along the tracks, where one set of rails turns into two sets (such as at a crossover or when there is a siding). At these points a switch can always be found and works exactly as it sounds: to switch the train over from one track to another or into a siding.

In old train films you might remember a conductor stopping the train, disembarking from his locomotive and manually switching the track. Now-a-days most of the switches are electrically-powered and can be switched remotely by a rail traffic controller.  As with all electronics, winter can cause power switches to freeze-up, so VIA has installed some handy-dandy heaters to help with that problem.

Several different types of heaters can be found on switches. Some use air-blowers to either blow the snow off the switch before it gets a chance to settle (cold air-blower) or melt the snow and ice once it has landed (warm air-blowers). These kinds of devices can be mostly along CN’s network of track. Along VIA’s track, electric elements are used. The elements are bolted onto the switches, and the heat transfer from the element to the rail melts the snow and ice. These have been found to be slightly more efficient that the air blowers, though both types will certainly do the trick!

These switch heaters are all automated: when they detect falling snow they turn on. But sometimes snow can be more difficult to sense, such as if it is drifting snow and not falling straight onto the rails. In cases like that, a traffic controller can override the automatic setting and manually turn on the elements. Again, this is all done remotely, so everyone can stay cozy and indoors even in the worst snowstorms!

Electric element heaters have been installed on the switches wherever VIA has added a siding or a section of third rail, funded through the Capital Investment program. Many sections of third track and new sidings can be found through the Alexandria, Kingston, Smiths Falls and Chatham subdivisions.

Visit our Tracks Projects or All Articles page to read more!