CTC questions....

This has been bugging me for some time and it hasn't been until now when I have asked this question....

On a line with CTC, does the CTC control switches in addition to signals? I ask this because I have seen instances where on a line with CTC, crews have had to manually operate switches. For instance, on Amtrak's Vermonter during the reverse direction move in Palmer (MA), crew members must exit the train and throw a switch get from the CSX line onto NECR tracks. Now the CSX line has signalling. Shouldn't it be a matter of just "calling the dispatcher on the phone" and getting the switch thrown? Another instance, a video I've seen of Guilford in Maine shows trains switching from the mainline to the Rumford Branch at Leeds Jct. This is CTC territory, yet it shows crews throwing the switch, and leaving it open.

So unless I get the concept of CTC wrong, shouldn't it be able to control switches and save time by eliminating hand-thrown switches? Enlighten me, please!

-Jay H.

Yes, in CTC territory the dispatcher can remotely throw the power switches. There is a situation where the dispatcher will loose communication with the switch control (switch out of correspondence). In this situation the dispatcher will communicate with the train crew and give them authority to take the power switch on hand and line it for the direction of movement. The switch is returned to power after at least one unit or car has passed over the switch (this varies with different railroads). The operating rule bounced around several times on the line I worked for, but the last I knew the stop indication of the signal governing movement over the power switch could be disregarded when the switch was on hand, but all movements had to be made at restricted speed. There are also hand thrown switches in CTC territory. These can be on industrial spurs or other side tracks and can be equipped with electric lock/unlock. Permission to operate the electric unlock and enter the main track must always be obtained from the dispatcher, but permission is not needed to operate the unlock and enter the side track from the MT (again, on the line I worked for). The dispatcher was to be notified when the switch was restored for movement on the MT and locked. Hope this helps.

Simply put, not all switches in CTC territory are remotely operated. Usually it is the ones located at "control points" (CPs). And as mentioned, many control point switches these days are "dual controlled" switches that can be either remotely operated or manually operated (with permision of the dispatcher, of course).

For the most part, dispatchers or operators do not directly control signals in CTC. What they do is align a route, then enable a signal to be displayed. The actual signal displayed depends upon occupancy of the track ahead of the movement. In other words, at a control point, the dispatcher "pulls up" the signal after aligning the route, but if the block ahead is occupied, the train being provided a route will get a "stop" signal, or at best a "restricting." Once the block immediately ahead clears, he will get an "approach." Once the second block ahead clears, he will get a "clear" or possibly an "advance approach."

You received a couple of great answers there Jay. Regarding Palmer specifically, the CSX interlocking is controlled by the "NA" dispatcher at Selkirk. The "NA" desk controls the main line from Boston to Springfield. The switch to the control siding at Palmer is controlled by "NA". The hand thrown switch from the control siding onto the yard lead is equiped with an electric locking device. That is the safety device described above. The Vermonter asks permission from the West Springfield Yardmaster (who also controls the CSX yard at Palmer) to enter the yard track from the control siding. Before the train departs CSX and enters New England Central trackage it obtains a Track Warrant to operate over the unsignalled portion of the NECR. The diamond crossing signal at Palmer is not directly controlled by CSX. When a train is within the block approaching the diamond the NECR crews cannot obtain a clear signal when the push the button in the signal box. If no trains are approaching the NECR crews can push a button in a wayside box and the signals on the CSX side will display "stop" and the NECR signal will display a "clear" signal that allows them to proceed. Hope that helps

Yes that does help, thanks everyone for the information.

-Jay H.