Collecting Signaling Related Issues For Boston Sprinter Route

Discussion in 'PC Discussion' started by NB642, Aug 27, 2021.

  1. NB642

    NB642 Member

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    After watching the last DTG stream, I understand that the next logical improvement for the route from Boston to Providence will be to address the somewhat problematic signaling (both wayside and in the cab). Here is a list of possible issues that I have noticed from my time trying out the services:
    1. This is an issue that almost everyone else has already mentioned, but the alert curve for ACSES will frequently activate much too early in advance of the actual location for a reduction in track speed. The worst offender is probably the approach into Providence.
    2. The dispatcher will set signals to stop just ahead of a scheduled station stop even though there are no trains ahead or blocked junctions. When running with cab signaling on, it makes it nearly impossible to maintain a tight schedule if you are running only 20-30 mph far in advance of a station.
    3. The positive train stop (PTS) function should only be active for "home" signals (including interlockings and control points). Distant signals, automatic block signals, and code change points should not enforce an automatic stop - theoretically you should be able to freely cruise by them at 20 mph when at their most restrictive aspect (which is Restricting) with ACSES and ATC on.
    4. In most cases, when inside a yard, there should be no cab signal higher than restricting and ACSES should not be enforcing any speed. There are exceptions of course, but the only places where you should be getting cab signals above restricting, civil speed enforcement, and positive stop enforcement is at the signalized exit of the yard to and from the mainline tracks. For example, I may be wrong, but I doubt that Pawtucket Yard has ACSES enforcing the 5 mph limit on all tracks in reality. This is similar to how the tracks are protected at 20 mph (restricting cab signal) at Boston South Station even though the posted speed is 10 mph.
    5. The use of the Approach Medium 30 cab signal indication seems improper for this route. It should really only be used for enforcing diverging speeds at switches that are specifically limited to 30 mph. It should not be used in the signal progression for a Stop/Stop and Proceed signal since the Approach Medium 45 cab signal in combination with the Approach cab signal would fulfil the role of bringing the train down to 45 and 30 mph respectively for non-diverging routes. (to be honest the only real usage for the Approach Medium 30 cab signal in my opinion, would be in territory without intermediate block signals where a distinctive warning is needed in advance of and passing through medium speed switches that would normally be protected by a visible distant signal, i.e. NORAC Rule 562 territory)
    6. The signals at Cove Interlocking may be incorrect. Approaching from the north, the pot/dwarf signal near the end of the platforms at Back Bay shows medium approach indication (low signal with yellow over flashing red), but the cab signals immediately drop to restricting - the proper cab signal would be approach. Approaching from the south, I seem to get a restricting indication (high signal with red over steady yellow) with cab signals almost immediately upgrading to clear (or approach medium? - I can't remember which). This is out of place since restricting is mostly used when diverging into unsignaled track (yard, siding, etc.). If this was meant to be medium approach, then it should show red over flashing yellow (this is a high signal) and should have a cab signal of approach.
    7. The signals on the Stoughton branch seem to prevent you from ever reaching the max speed of the line. You are limited to 30 mph by an approach signal and brought down to restricting by a pot/dwarf signal on one of the sidings. Is this really supposed to be the case? It certainly makes it hard to be on time with the current timetable.
    8. I already mentioned this on another thread, but the MBTA aspect display unit is not working correctly. Both the F40 and CTC-3 cab ADU's have the "90" and "MAS" balloons lit up at the same time for most of the route when signals are clear. This is not accurate. The ADU can only display one aspect at a time, so it should either have the "90" or the "MAS" balloons lit but not both at the same time. For reference here are the codes associated with each cab signal:
      • 180 ppm / 180 ppm: should have "MAS" lit (this corresponds to "CLEAR 150" for Amtrak trains)
      • 180 ppm / 0 ppm: should have "MAS" lit (this corresponds to "CLEAR 125" for Amtrak trains)
      • 270 ppm / 270 ppm: should have "90" lit (this corresponds to "CLEAR 100" for Amtrak trains)
      • 120 ppm / 120 ppm: should have "80" lit (this corresponds to "CAB SPEED 80" for Amtrak trains)
      • 270 ppm / 0 ppm: should have "60" lit (this corresponds to "CAB SPEED 60" for Amtrak trains)
      • 120 ppm / 0 ppm: should have "45" lit (this corresponds to "APPROACH MEDIUM" for Amtrak trains - used for both Approach Medium and Approach Limited wayside signal aspects)
      • 75 ppm / 75 ppm: should have "30" lit (this corresponds to "APPROACH MEDIUM" for Amtrak trains - relatively new cab signal to differentiate between Approach Medium from Approach Limited)
      • 75 ppm / 0 ppm: should have "APP" lit (this corresponds to "APPROACH" for Amtrak trains)
      • 0 ppm / 0 ppm: should have "RES" lit (this corresponds to "RESTRICTING" for Amtrak trains)
      • 0 ppm / 0 ppm at interlocking or other signal where positive stop is enforced by ACSES: should have "STOP" lit (this corresponds to "STOP" for Amtrak trains)
    These are the points I could gather for now, but I will definitely add to the list if I find more specific cases for signal errors/inaccuracies.
     
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  2. NB642

    NB642 Member

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    Update: For Item (7) above, I now realize that the Stoughton Branch is NORAC rule 562 territory (no fixed ABS signals) - so we should have more code change points between Canton Junction and Stoughton Station. I think this reinforces the point that we should be getting better signals and cab signals than approach and restricting (at least before the end of the tracks).
     
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  3. Mat_Jam_Ca

    Mat_Jam_Ca Well-Known Member

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    That’s a detailed list. Very interesting too.
     
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  4. chieflongshin

    chieflongshin Well-Known Member

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    I’ve noticed this morning on two of the depot to station moves with the cab car In boston (early 3 and 4 am ) services you’ll get to the last signal before the station and It will be red . The go via marker is about 20 yards from red signal. I sat at this go via marker for about 20 mins earlier. I noticed that you have to almost roll up onto the signal for it to change.

    I think it’s changing perhaps a tad too late or the go via needs moving . If you hit that go via about 10mph you can just about have it amber as you meet it, anymore and you spad
     
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  5. NB642

    NB642 Member

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    I have noticed similar behavior with the regular services too approaching Boston (Amtrak trains from Back Bay). It seems that the dispatcher signaling priority is directly linked to the placement of these go via markers (as well as possibly the station stops themselves).
     
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  6. jeff.engle

    jeff.engle Member

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    Thank you for the detailed list. Nice to know that I’m not the only one seeing some of these issues.
     
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  7. Jinoss17

    Jinoss17 Well-Known Member

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    Just hats off for your dedication. I would never do that myself.
     
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  8. cActUsjUiCe

    cActUsjUiCe Developer

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    This is pretty much the same list we're tracking internally. Keep it going and great job!
     
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  9. NB642

    NB642 Member

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    Great to hear and thanks to you and the rest of the team for keeping track of these points! These were the items that caught my attention, but I will certainly try to add on if I spot anything else.
     
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  10. Ravi

    Ravi Active Member

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    This is a great list. Thank you. I have also had the issue with the stop times when keeping up with ATC. hopefully DTG fixes it soon.
     
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