What Do Amtrak's "Signal Issues" Entail? - July 3, 2023 Delays on the NY - NJ Stretch of the NEC

What exactly do signal problems entail? Are they displaying incorrect aspects? Not turning on at all?
Cab signals malfunctioning? All of the above?

After reading about these delays and narrowly missing them, the universe decided it was my time to experience one of Amtrak’s infamous “signal Issues" yesterday July 3, 2023.
I have a YouTube video you can watch to follow along: https://youtu.be/Nw0tiw0s8hI
Timestamps are available so you can skip around.
Sidenote, can someone assist with embedding YouTube videos?
I tried to but I got a message saying "You cannot use certain BBCodes: "

I was on Amtrak Keystone Service 609. All was swell until arguably BERGEN interlocking, where we began slowing down. I didn’t sweat anything because I thought maybe a NJT train was diverging and we’d overtake it at Secaucus. But, we never overtook anything. We came to a halt at DOCK interlocking behind a NJT train.
We moved up to the DOCK drawbridge right outside of Newark Penn and waited for quite some time.
A number of NJT trains passed us slowly and platformed on track 4.
For a surprise, a westbound Acela arrived on TRACK 2, first time seeing a westbound train use that track.

From there, our track pathing (if you call it that) was weird. We diverged from 3 to 2 at CLIFF, then back to 3 at HUNTER.
We stopped at LANE interlocking and a few NJT trains passed us. We wound up catching up and passing them around Elizabeth and ELMORA.
Then we switched over to 4 at ELMORA, then finally back to 3 at the western end of FAIR after leaving Trenton.
The stretch between DOCK & LINCOLN was start & stop with restricting speed. Once we hit LINCOLN we picked up track speed, and maintained around 100 MPH.
I noticed between ELMORA & FAIR, literally every train was only on 1 or 4. Like 2 & 3 were OOS.

We departed NYP at 12:54PM and arrived in PHL at 5:15PM.
But here’s the good news, you can read about it (here & it's all over the news) and / or skip through my video.
I had to sit there for 4+ hrs. I’m not upset at all, and made the best of the situation.
But I do realize 99% of the passengers didn’t share my sentiment, and I understand as I’ve been in their shoes before.

Anyways, if anyone could shed some light (preferably position light, but color position works too ) on Amtrak’s signal issues and what they entail, I’d appreciate it.

Also, if the moderators feel the need to move this thread into the "delays" one, feel free.
I made this one because I was more interested in what "signal issues" entail than the delays themselves.

From what I heard, it was a track circuit issue that affected 20 miles or so of track. Dispatcher was unable to display signals at the interlockings so trains needed verbal permission past stop signals. Can only run restricted speed with no signals so running 20 max for 20 miles will cause substantial delays. I’m not qualified on the territory or a C&S employee so I only have a general idea of what happened from working the other side of the corridor.

8th Notch wrote: ↑Tue Jul 04, 2023 6:28 pm From what I heard, it was a track circuit issue that affected 20 miles or so of track. Dispatcher was unable to display signals at the interlockings so trains needed verbal permission past stop signals. Can only run restricted speed with no signals so running 20 max for 20 miles will cause substantial delays. I’m not qualified on the territory or a C&S employee so I only have a general idea of what happened from working the other side of the corridor.

Oh wow. That's interesting. I'm not really familiar with HOW signals work. I thought they were automatic & oversaw by humans. As in wayside aspects would change accordingly, and dispatch would intervene for unorthodox situations, and terminal / yard moves. Or should I say I have a rough idea of how signals work in theory, but the human involvement aspect was something I was unfamiliar with. The restricting MAS made a ton of sense, along with the verbal commands from dispatch to move trains. I couldn't see the signals well from my seat, but I wonder if the signals weren't showing anything or if they all had incorrect / stop displays.

Hats off to the dispatch team, that job is NOT easy. Diverging moves with signal issues reminds me of my struggles with calculus. Ok, perhaps a bit harder than that.

Thanks for sharing.

Sidenote, I noticed quite a few locomotives had their doors open. Even the Amtrak ACS-64s, I say that because they're newer and I thought they would have state of the art AC. Even that guy from Wilmington who lives in the big house had a tour of one. I've never been in a locomotive before (Train Sim World & Trainz simulators don't count ) but I guess it can heat up in there. One ALP-46 that was leading a consist had its shades pulled down. YIKES.
I also think the engineer of my train (it was lead by a Metroliner cab car) left the cab for a minute because of the heat.

Yeah, when the signals go down, all tracks go into "safe manual block" operation. Basically, 15 MPH limit between visual signal posts, no cab signals, keeping an eye out for anything on the line. They probably also got trains onto a dedicated northbound and a dedicated southbound track until they were out of the affected territory.

There was a same down in Baltimore in which lightning took out signal power between GROVE and CHARLES interlocks. Trains were crawling all the way down to near Odenton (GROVE) where signal power was back up and they could get back to speed. Needless to say, a TON of MARC trains were canceled that day and some turned short during that afternoon rush hour.

Signal power loss between Lincoln and Lane.

NortheastTrainMan wrote: ↑Tue Jul 04, 2023 7:22 pm

8th Notch wrote: ↑Tue Jul 04, 2023 6:28 pm From what I heard, it was a track circuit issue that affected 20 miles or so of track. Dispatcher was unable to display signals at the interlockings so trains needed verbal permission past stop signals. Can only run restricted speed with no signals so running 20 max for 20 miles will cause substantial delays. I’m not qualified on the territory or a C&S employee so I only have a general idea of what happened from working the other side of the corridor.

Sidenote, I noticed quite a few locomotives had their doors open. Even the Amtrak ACS-64s, I say that because they're newer and I thought they would have state of the art AC. Even that guy from Wilmington who lives in the big house had a tour of one. I've never been in a locomotive before (Train Sim World & Trainz simulators don't count ) but I guess it can heat up in there. One ALP-46 that was leading a consist had its shades pulled down. YIKES.
I also think the engineer of my train (it was lead by a Metroliner cab car) left the cab for a minute because of the heat.

The locomotives do have AC, some people just have a personal preference to open the doors and windows.

The ACS A/Cs work amazingly well. Few minutes at 65 and your cold

The Wikipedia article on pulse code cab signaling (taken with a grain of salt, since it could be inaccurate) describes how the actual code pulses used by the ACSES cab signaling system in the trains are injected into the running rails. The key point described in the article is that the pulses are injected using the AC track circuits used to detect the presence of the train. Loss of signal power would not only disable the track circuits but the code generators and injectors too, resulting in the ACSES system displaying a Restricting aspect as described above.

Is there any information on how the signal power loss occurred? My understanding (likely wrong) was that Amtrak had installed a large number of static frequency converters at the various traction substations to provide an alternate power source for the 6.9kV 91.67Hz signal power main that was utility-backed, to protect against a loss of traction power knocking out the signalling systems and the interlockings.

TheOneKEA wrote: ↑Fri Jul 07, 2023 8:30 pm The Wikipedia article on pulse code cab signaling (taken with a grain of salt, since it could be inaccurate) describes how the actual code pulses used by the ACSES cab signaling system in the trains are injected into the running rails. The key point described in the article is that the pulses are injected using the AC track circuits used to detect the presence of the train. Loss of signal power would not only disable the track circuits but the code generators and injectors too, resulting in the ACSES system displaying a Restricting aspect as described above.

Is there any information on how the signal power loss occurred? My understanding (likely wrong) was that Amtrak had installed a large number of static frequency converters at the various traction substations to provide an alternate power source for the 6.9kV 91.67Hz signal power main that was utility-backed, to protect against a loss of traction power knocking out the signalling systems and the interlockings.

Not a signal maintainer just make them stop and go. Cab signals do work off the code received by the locomotive through the rails. This is done by cab signal pick up shoes over the running rails there could be two or four shoes depending on type of locomotive.
ACSES is a safety overlay and functions with the cab signals, when your trackside and you see those yellow boxes between the rails. They are the ACSES system pucks, antenna underneath the locomotive pick up the signal and display it on the ADU along with our cab signal. The loss of ACSES would not cause the loss of cab signals, although lately with the GEs anything is possible.. One would have to slow down to the prescribed speed depending on railroad either 79 or 59mph retesting the system after 2 miles. The cab signal system will/should function as intended.
As for what when why and how the

During the early mornings of the 6th and 7th there were catenary outages in roughly the same area as
the signal outage on the 3rd. Wonder if there was a common cause?
Andy

twropr wrote: ↑Sat Jul 08, 2023 1:17 pm During the early mornings of the 6th and 7th there were catenary outages in roughly the same area as
the signal outage on the 3rd. Wonder if there was a common cause?
Andy

Good question. The NJ section of the Northeast Corridor has been going through it this week.
My guess is the heat had something to do with it. The last few times catenary outages occurred there, the heat was a factor.

CSRR573 wrote: ↑Wed Jul 05, 2023 11:22 pm The ACS A/Cs work amazingly well. Few minutes at 65 and your cold

Nice, I'd like to sit in one during these summer months. Oh, and the view would be nice too .
Also, thanks to 8th Notch for chiming in about the A/C in the locomotives.

Part of me was concerned because there was a NJT engineer who operated a ALP-46 in the summer with broken A/C and sustained career ending & life altering injuries, here's the full article -> https://www.trains.com/trn/news-reviews ... otive-cab/

Granted that was an extreme case. So with my limited knowledge, when I saw those locomotive doors open, I thought the engineer & crew in them were in bad shape. Glad to hear that wasn't the case.

Instead, it looks like some engineers like the breeze from time to time.

CNJGeep wrote: ↑Wed Jul 05, 2023 11:52 am Signal power loss between Lincoln and Lane.

That sounds about right. I guess it was easier to keep only 1 & 4 in service for most of it.
Tracks B & A were in service between ROADS & ELMORA as well.

Is ROADS the new designation for what was the west end of UNION? I know Amtrak has been giving separate names to parts of large interlockings.

Railjunkie wrote: ↑Sat Jul 08, 2023 7:43 am

TheOneKEA wrote: ↑Fri Jul 07, 2023 8:30 pm The Wikipedia article on pulse code cab signaling (taken with a grain of salt, since it could be inaccurate) describes how the actual code pulses used by the ACSES cab signaling system in the trains are injected into the running rails. The key point described in the article is that the pulses are injected using the AC track circuits used to detect the presence of the train. Loss of signal power would not only disable the track circuits but the code generators and injectors too, resulting in the ACSES system displaying a Restricting aspect as described above.

Is there any information on how the signal power loss occurred? My understanding (likely wrong) was that Amtrak had installed a large number of static frequency converters at the various traction substations to provide an alternate power source for the 6.9kV 91.67Hz signal power main that was utility-backed, to protect against a loss of traction power knocking out the signalling systems and the interlockings.

Not a signal maintainer just make them stop and go. Cab signals do work off the code received by the locomotive through the rails. This is done by cab signal pick up shoes over the running rails there could be two or four shoes depending on type of locomotive.
ACSES is a safety overlay and functions with the cab signals, when your trackside and you see those yellow boxes between the rails. They are the ACSES system pucks, antenna underneath the locomotive pick up the signal and display it on the ADU along with our cab signal. The loss of ACSES would not cause the loss of cab signals, although lately with the GEs anything is possible.. One would have to slow down to the prescribed speed depending on railroad either 79 or 59mph retesting the system after 2 miles. The cab signal system will/should function as intended.
As for what when why and how the

Thanks for the additional context! The Wikipedia article on ACSES states that it can function independently of the cab signaling system and explains some of the methods that are used. It also says that ACSES will enforce a positive stop at an absolute stop signal, so I’m curious to know how the ACSES system reacts when the pulse codes go offline while the locomotive is in motion.