• Signal situation at Amtrak UNION interlocking

  • General discussion about railroad operations, related facilities, maps, and other resources.
General discussion about railroad operations, related facilities, maps, and other resources.

Moderator: Robert Paniagua

  by Bobinchesco
http://www.youtube.com/watch?v=FNNKplA1 ... ure=relmfu

In this Youtube video taken at Rahway, apparently during the evening rush, westbound trains are operating on no. 2 track. I think that they are going into the Eastward Tunnel Track. At first the 2S signal at UNION is displaying MA, as the Coast Line dispatcher is not yet pulled up at GRAW. However, when he does pull up the 2S goes to LC. This concerns me as the tunnel tracks are 30 mph. With the home signal at LC, the distant will display AL. However, AL on the distant does not necessarily mean that the home will be LC, as I believe this is three block territory. Presumably, engineers operating Coast Line trains are aware of this and operate their trains appropriately. But what about a possible misroute of a scheduled through train (hey stuff happens). That engineer seeing AL on the distant might expect he is going to cross to no. 3 or at worst has a SS or S&P two blocks ahead, not go diving into the hole. Any qualified engineers care to comment? Budd, JT?
  by Jtgshu
Until very recently now that Amtrak has rebuilt the switches in the Interlocking, you would get a Limited Clear to a 15mph crossover. Amtrak has since rebuilt the crossovers, and they are no longer 15mph (actually two of them) There are some really wacky things they have done with the signals in that area, and none of it makes any sense. I can't wait to see how bad they screw up Dock when they CETC it.....they really destroyed Union with taking out all the interlocking signals and moving Home signals...especially with moves to and from the Coast Line
  by amtrakhogger
C&S took out all the "pockets" at Union and you now only have one signal governing your movement through the interlocking. Sometimes with the signal system you may have a signal that gives speed greater than the what is allowed for the track and so engineers must be governed accordingly.
  by ExCon90
I thought a major feature of ACSES, if not the whole point, was to build permanent speed restrictions into the cab signals to make it impossible to receive a more favorable indication than civil speed restrictions permitted. It doesn't sound like that's happening at UNION. Are they planning to play catch-up later?
  by Bobinchesco
ACSES was originally implemented only between COUNTY and HAM. I don't know if it has been extended yet, but it will need to be in order to comply with PTS deadline.
  by MikeEspee
Speed signaling logic in its most basic form operates to convey turnout speed approaching and at a given interlocking, as well as a calculated braking distance with intermediate signal spacing to comply with downgrades in signal indications to and including a stop signal. All permanent and temporary speed restrictions at any given location are OMITTED from the defnitions of the signals and requirements of the signal logic. Speed signals convey three and ONLY three true turnout speeds. Limited, Medium and Slow... Everything else we need to know, we have with our knowledge of the physical characteristics of the territory we operate. It's because someone thought they could go 45 through the tunnel tracks on a limited clear that ACSES is being implemented...

And it is a basic fundamental rule of railroad operations WHY these things are the way they are: The Rulebook is the rulebook, in it are definitions of signal indications, for example. The rulebook is amended by the timetable which contains, among a hell of a lot of other things, permanent speed restrictions and maximum authorized speeds for the territory. The timetable and rulebook are amended by bulletin orders containing weekly and monthly timetable and rulebook changes. Rulebook, timetable and bulletin orders are amended DAILY in real time by Form D or other mandatory directives and TemporarySpeedRestrictionBulletins on the NEC. The temporary speed restriction found on your daily TSRB for the tunnel tracks amends not only the timetable but the very rulebook that says "go 45mph here with this signal".

So to reitterate: signal logic doesn't provide for temporary speed restrictions such as the former 15mph on the tunnel tracks. There was no limited speed signal into a 15mph turnout... All the signal controller sees is there are no trains in the block, the next signal at Graw is lined up and the switches are lined and 'locked' in whatever appropriate position. The least restrictive signal indication that situation warrants will be displayed, regardless of permanent or temporary speed restrictions within or near the home signal. If the switches are good for 45mph, you WILL get a limited clear. If you're looking at a limited clear on the home signal and think "why doesn't the dispatcher give me a slow approach?" go back to railroad 101 class
  by Jtgshu
Mikeespee, I understand what you are saying, but that doesn't mean the proper signal logic has been applied, which IMO is the case at "the new and improved" Union.

There was a restriction in the timetable of 15mph on the crossover from Track 4 to the Westward Tunnel Track (Westbound Hole) at Union, as well as the Track 3 to the Eastward Tunnel Track (Eastbound Hole) crossover. Its been there for a LONG time. More recently, they has Temp Speed Restrictions on the tunnel tracks themselves of 15mph. So no matter what the signal said, (it used to show a Medium Clear - allowing 30mph) you had to go 15 going over those crossovers, because of the permament speed restriction in the timetable and then 15mph because of the temp speed restriction on the tracks past (RR west) of the crossovers to Graw interlocking.

They rebuilt the Tunnel tracks from the ground up and they put new switches and crossovers in at Union over the past year or so. They were able to get rid of the temp speed restriction of 15mph on the Tunnel tracks and they put the new signals in as well. However, they cut the new signals in BEFORE they finished the track work, so the restrictions were still in place when the signals were upgraded to now slowing a Limited Clear (45mph) for the track which still was restricted to 15mph BY TIMETABLE and 15mph west of it as a Temp Speed Restriction. only relatively recently has the 15mph permament timetable restriction for the crossovers been lifted, but the track west of it is still 30mph. So why are they giving a Limited clear to now 30mph track. Yes, its better than a Limited Clear to 15mph crossovers and track, but still, when most other crossovers in the interlocking are medium speed and show a Medium Clear - why are these allowing by signal 45mph. And if one were to take those crossovers at 45mph you would run the risk of ending up on your side. They are NOT 45mph Xovers....and if they somehow are, i would NEVER go anywhere close to 45mph going over them. But more importantly, what if the train is misrouted - you are seeing a Limited Clear and don't know you are routed to a 15mph crossover? Thats potential for disaster right there, because of ACSES? Thats progress......

All while at the same time, the crossover from track 1 to A in Rahway station now apparently is good for 15mph only. before it and the signals were rebuilt, it was good for 30mph. The new signals put in, now you get a slow approach at Unions home signal when crossing over there (then yelled at by the dispatcher because they wanna know whats taking so damn long....). Now they have rebuilt the crossover itself and it sure looks like a 15mph crossover now as its tighter than it was before. So in this case, the opposite is going on. They are using the signals to enforce a speed restriction that is NOT in the timetable. I know how the signals work and what the dispatcher can and can't do. But some of these people who design these "new" signals seem to be lacking in common sense as well and an understanding of what the signals actually do and mean to the engineers who are running the trains.