• Who controls the switches?

  • Discussion relating to commuter rail, light rail, and subway operations of the MBTA.
Discussion relating to commuter rail, light rail, and subway operations of the MBTA.

Moderators: CRail, sery2831

  by Yellowspoon
 
In this particular question, who is the person who pushes the button or throws the lever that makes the switch(es) move to the desired position?

Forty years ago, there was a button on Green Line trains that the operator would push if (s)he wanted to go to the right at a switch. I believe that now the operator sets a dial as to his/her destination and a trackside reader automatically sets the switch as the operator passes near the trackside reader. I assume these are placed only where scheduled trains normally diverge (e.g. Boylston, GovCen, NorthStation (eastbound), Park, Copley, Kenmore, and Beacon Junction(westbound).

How about seldom used switches? For example, during baseball games, they usually run a car from Blandford to Park. Is the switch into the pocket track at Blandford automatic or is it manually controlled from trackside? Are yard switches all manually controlled at trackside? What about the Kenmore loop?

During normal operations(?) at Cleveland Circle, someone manually flips the switch with a crowbar(?) twice for each train, once when the train enters the tail track, and again as the train leaves the tail track. This switch is moved more than the outbound switch at Beacon Junction. Shouldn’t this be automated?

What about a Red Line train heading to Alewife. The operator has no a priori knowledge as to which (if any) platform track is vacant. Also, it’s possible that two Ashmont trains arrive consecutively, so the departure is not necessarily first-in-first-out.

What about trailing switches? My recollection is that 50+ years ago, the trains on n Green Line merely pushed the switch as it went by if necessary. Is this still done? Was that the case on other lines?
  by MBTA3247
 
Yellowspoon wrote: Mon Sep 21, 2020 9:00 am In this particular question, who is the person who pushes the button or throws the lever that makes the switch(es) move to the desired position?

Forty years ago, there was a button on Green Line trains that the operator would push if (s)he wanted to go to the right at a switch.
That was a shunt that provided a current load in the detection block immediately ahead of a switch in places where providing a load by accelerating the car was undesirable.
I believe that now the operator sets a dial as to his/her destination and a trackside reader automatically sets the switch as the operator passes near the trackside reader. I assume these are placed only where scheduled trains normally diverge (e.g. Boylston, GovCen, NorthStation (eastbound), Park, Copley, Kenmore, and Beacon Junction(westbound).
Correct.
How about seldom used switches? For example, during baseball games, they usually run a car from Blandford to Park. Is the switch into the pocket track at Blandford automatic or is it manually controlled from trackside? Are yard switches all manually controlled at trackside? What about the Kenmore loop?
I don't offhand know about the Kenmore loop, but the Blandford siding and all yard switches are manual operation.
During normal operations(?) at Cleveland Circle, someone manually flips the switch with a crowbar(?) twice for each train, once when the train enters the tail track, and again as the train leaves the tail track. This switch is moved more than the outbound switch at Beacon Junction. Shouldn’t this be automated?
Yard trackage is too tightly spaced and the potential routings too complex to automate. Even adding a switch motor with a push button mounted on a nearby pole is not worth the effort, as it's another point of failure that the T doesn't need.
What about a Red Line train heading to Alewife. The operator has no a priori knowledge as to which (if any) platform track is vacant. Also, it’s possible that two Ashmont trains arrive consecutively, so the departure is not necessarily first-in-first-out.
Those switches are controlled from the central operations center.
What about trailing switches? My recollection is that 50+ years ago, the trains on n Green Line merely pushed the switch as it went by if necessary. Is this still done? Was that the case on other lines?
That was only ever done on the Green Line, and only with single-point switches (which use a spring mechanism to hold the point in whatever the last set position is). While there are still plenty such switches in service (mainly in yards), this is not recommended practice, and I noticed during my last few visits to Lechmere that they were always throwing the switches there manually before running cars over them.
  by CRail
 
Kenmore loop is operated by a wall mounted button. Car comes in, Kenmore official points to the right indicating the direction the car is to head in (or the Dispatcher notifies the operator they'll be looping Kenmore, OR for game nights or other special events the operator already knows they're looping Kenmore...), the crew kicks everyone off the train, hits the button on the wall, gets the diverging signal and goes up into the loop. Every AVI (automatically) operated switch can be overridden by a wall mounted pushbutton. Say, for instance, a Cleveland Circle train gets delayed at Park Street right in front of a Heath Street train. The E train is instructed to "take the fence" (the inside track at Park St.) to go around the C train, the operator can cancel the automatically selected route and select the desired diversion. Every once in a while the AVI will mess up and either not work at all or send a train the wrong way and the route will have to be selected manually. It's rather alarming to be on your way to Prudential and get the straight arrow signal at Copley!

All switches on the surface (Highland Branch excepted) are hand throw only.
  by bostontrainguy
 
And in the good old days you could run through a trailing spring switch without stopping (like where the C Line cars loop into the yard on Chestnut Hill Ave). Now the operators are required to throw every switch by hand often holding up traffic coming down the hill into Cleveland Circle. "Slapping" switches will get you in big trouble.
  by Arborwayfan
 
In 1986-89 and for a while after that Brigham Circle was set up with two spring switches, so that each car could pull into the outbound platform, change ends, and head over to the inbound platform without throwing any switches. I think. I remember watching a car do it. Sometime later they moved the crossover inbound of the inbound platform, so a car turning back to downtown at Brigham Circle would now, I guess, use only the inbound platform, but the same staggered platforms are still there. Does anyone know why they moved the crossover?

One would not call Oslo backward in street-running trolleys, and the #19 and #12 cars' operators have to throw the switch at Majorstuen at the beginning of every run (assuming they are alternating, which they normally do. They don't use a crowbar to pry the rail over; there's an underground switchstand under a plate between the rails, with a place to inset a kind of extension into the lever that makes it work; they get off the car with the lever and throw the switch. Takes half a minute and gives the operator a chance to stretch. No reason to automate. But there's no backup move involved and the cars are scheduled to sit at that station for a few minutes anyway, so there's no delay.