Rail and switch review

I found a picture that I’d taken a while ago of switches near Rose Quarter- it probably should have gone in my last post but I’ll put it here and make this a review post about switches and rail types. First: rail types.

Borrowed picture which shows cross-sections of both types of rail used on the MAX alignment: t-rail on the left, girder rail on the right. Girder rail is used in lower speed areas (CBD/downtown & Holladay, Washington Street in Hillsboro), and t-rail is used everywhere else. Along Interstate, the t-rail is embedded in pavement so it looks similar to girder rail. This picture shows the embedded rail on Interstate along with the crossover switches that are not embedded.

Here is the picture of Rose Quarter, where girder rail is what’s used:

Switches, looking east from the westbound platform at Rose Quarter

This picture shows the different routing options available on the eastern side of the Rose Quarter platform. The nearest track is the westbound mainline, the one diverging off to the left side of the picture leads to the trolley barn, the one that’s actually a straight route from the westbound mainline is the special events track, and the far track is the eastbound mainline. In this type of rail, the only way to tell how switches are set is by observing the switch points – while the ABS/combination signals associated with these switches tell you what the route is, it’s still necessary to observe that the switches are set properly.

West Ladder, Elmonica Yard

Compare the switches at Rose Quarter to these in the Elmo yard, facing the storage tracks. These t-rail switches are power switches, meaning they can be thrown remotely from the cab of a train, and they have switch indicators (green for switches set normal, yellow for switches set diverging – remember manual switches in t-rail use targets with the same colors). You can see how the color of the indicator matches how the switch points are aligned. Girder rail switches don’t have indicators like these to make it easier to tell how the switch points are set, but even with indicators it’s still always necessary to observe switch points – an indicator can be wrong, but switch points never are.

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4 responses to “Rail and switch review

  1. Fascinating as usual! Just love this stuff!!!

  2. Looking at the Elmo picture, it looks like you use a route code to select the storage track. A cab photo shows “L”, “R”, “C” and “Call” buttons. Is “C” the call cancel? What are the “L” and “R” for? I thought the “L” and “R” buttons were used to control switches around the yard — but maybe I’m not recalling this correctly.

    • Yes, the third button (sometimes it’s blank) is used to cancel a selection.

      You use both the L & R buttons and route codes/call button to get around the yards. L & R are only used in some parts of the yard (e.g. in the throat at Ruby, if you zoom in on the picture you can see the L-R sign. They’re also used in one of the quadrants at Elmonica).

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