Monthly Archives: July 2010

Anatomy of a MAX car, Part 1

And now.. a reference post describing a train car in detail, so if I refer to any part of it by its name in another post, you’ll know what I’m talking about.

Type 1, 2, and 3:

The cars are symmetrical, so it wouldn’t be helpful to describe them by “front end” or “back end” – so instead there is the A-end and B-end.  C is the section in the middle, because we enjoy being difficult like that.

A-end of 326

A cab of 326

B-end of 326

B cab of 326

Same car, different ends

Type 4s:

Not symmetrical since there is only one cab per car.  So the cab is always the A-end, and the parlor area where passengers can sit is always the B-end.

Car 412 A-EndCar 412 A-End

Car 420 B-endCar 420 B-end

On top of the train is the pantograph. In the Type 1s, 2s, and 3s, the elbow of the pantograph points towards the B cab and the open part points towards the A cab – it’s the quickest way to tell when you’re outside the car which end is A and which end is B, which is necessary for some troubleshooting procedures.

Car 304Car 304, coupled at its A end

Type 4Pantograph on the Type 4 – notice how it points to the cab, which is the A end

In the Type 4s, that’s reversed – the open part of the pan points to the B-end and the elbow points to the A-end, because as I said, we enjoy being difficult. But it’s always easier to tell which end of the 4 is A and which is B, since only A has a cab.

Doors and Bridgeplates

Type 2 with bridgeplates outType 2 with doors open and bridgeplates deployed

Every door in a train car is numbered from 1 to 8, with door 1 being the first door on the left facing the A cab and door 8 being the last door on the right.  On the right side (facing the A cab), doors 4 and 6 on the low-floor cars (Type 2, 3, and 4) are bridgeplate doors, and on the left, doors 3 and 5 are bridgeplate doors.  The bridgeplate is the ramp that can be deployed to assist passengers in wheelchairs or other mobility devices in boarding and exiting the train.

Emergency intercoms

The passenger emergency intercoms are push-to-talk intercoms used if there is an emergency on board the train.

Good things to use this button for – alerting the operator if a passenger has a medical emergency, if something happens that requires police involvement, smelling something burning onboard the train, spotting something that looks like it could be a mechanical failure on the train, etc.

Bad things to use this button for – a shiny thing for your toddler to press, as a means of asking the operator what time it is or if this train goes downtown, or as a means of asking the operator for advice on your romantic life. Yes, that has happened.

Type 1 IntercomIn the Type 1s, you can find the emergency intercoms to contact the operator by looking above the seat located to the left of the cabs.

Low-floor intercomIn the Type 2s and 3s, the intercoms are located near doors 3, 4, 5, and 6.

In the Type 4s, there are intercoms at doors 1, 4, 5, and 8.

Reader boards

The reader boards are the displays in the train that show the name of the next stop (connected to the APACU, which is the automated audio/readerboard announcement system, and maybe I’ll give that its own entry in the future)

Readerboard, Type 2Type 2/3 Reader board

Readerboard on a Type 4Type 4 Reader board

Type 1s have no readerboards.

If the readerboards are dark or aren’t showing the right stop, let the operator know – it’s not always obvious from the cab if the readerboards aren’t working right.

More to come..

Pantographs and the Overhead Wire

All about the pantographs, baby

PantographThis is a pantograph.

The pantograph, frequently abbreviated to “pan”, is the spring-loaded arm that’s part of how the train draws power from the overhead wires, aka catenary.

pantograph at Sunset TCBy design, the pantographs press upward on the catenary. Where there isn’t a lot of clearance between the catenary and the train, the pantograph folds nearly flat on itself, as seen here at Sunset Transit Center.

The bow collector (presumably named that because it’s shaped like a bow) at the top of the pantograph arm is topped by a carbon shoe, which is the part that directly contacts the wire (which, not coincidentally, is called the contact wire). The carbon shoe is gradually worn down by the overhead wire and eventually needs to be replaced. To wear it down evenly, the overhead wires zigzag back and forth instead of going in a straight line which would only wear down one part of the carbon shoe and potentially break the pantograph.

This is not a TriMet video, though I’d love to set up a camera on top of a MAX train to get something similar – it shows both how the spring-loaded pan rises and falls depending on how much distance there is to the wire above as well as the back-and-forth zigzagging of the wires so that the carbon shoe wears evenly.

The Overhead Wire, aka Catenary

The overhead wire ranges in voltage from 675-925 volts, averaging around 750 volts, direct current.  In other words..


I used to have a link here to a Philadelphia news article where a 15 year old climbed a cat pole to touch the overhead wire but the link expired. He survived but was severely burned. A simple Googling shows a lot of fatalities that happened when people climbed on top of trains or up cat poles to touch the wires or the pantograph. I shouldn’t have to say “don’t touch something high-voltage” because it should be obvious that that’s a really bad idea, but I’m all about spreading the safety message even when it means stating the obvious.

Low-speed and high-speed areas

CBDCBD near PGE Park

In low-speed areas, such as downtown Portland or in the yards, a single-wire trolley system is used. Throughout the downtown alignment, you’ll see how the contact wire is a single wire strung through other supporting wires.

East of Beaverton Transit Center

In high-speed areas, the overhead wires look like this. The upper wire is called the messenger wire, which supports the lower contact wire.

On some of the catenary poles, you’ll see tension weights hanging. I’ve already gone over how the weights work in another post – but to summarize, they rise and fall as the temperature changes to keep tension in the overhead wire.

Section Isolators

Section isolator, CBD

Section isolator, near Beaverton Transit Center

Throughout the alignment are section isolators (also known as section insulators) in the overhead wire. These unpowered breaks in the line allow for power to be turned off in one area without needing to shut down the entire system. To prevent arcing and other problems, a MAX operator going under an isolator won’t draw power until both pantographs are clear of the isolator.

I’ve seen brighter sparks than this, but they’re extremely hard to photograph.

arcBetter example of arcing

Those pictures are examples of arcing downtown where the Yellow-Green alignment crosses the Blue & Red alignment. If you’re on a train going through where the lines cross over and all the lights in the train go out briefly, this is why. Arcing is not a desirable phenomenon, and excessive arcing can sometimes be indicative of a very serious problem.

It seems that pictures of arcing between pantographs and overhead wires is a popular topic that people search for, so I’ve added some additional photos of arcing.  And then I added some more!

Willow Creek, looking westWillow Creek, C and P signs (click for larger to see the P sign)

As a visual reminder of where the section isolators are in high-speed areas where a train is likely to be in a propulsion mode greater than those used in low speed areas, there are C and P signs along the alignment associated with the isolators. When the front of the train reaches the C sign which will be located prior to the isolator, the operator must coast, and therefore not draw power from the catenary until reaching the P sign, at which point the operator can resume a propulsion mode drawing power because both pantographs have passed beyond the isolator.

Willow Creek IsolatorWillow Creek C sign and section isolator

In most sections of the alignment, unless you know the isolator is there, you most likely won’t be able to feel the train going into coast and back, but offhand I can think of two sections where it’s fairly obvious to passengers – westbound out of Willow Creek (where this picture was taken) and eastbound out of Sunset. At Willow Creek, the isolator is so close to the platform that the train will not pick up much speed before the operator must coast, so westbound departures from Willow Creek often feel very slow.

Sunset eastboundEastbound from Sunset Transit Center

At Sunset, the isolator is on an upward hill – note the C sign at the base of the hill – so gravity is working against the train coasting uphill and you can feel a slight jerk and drop in speed as the train goes into coast. If the operator doesn’t pick up enough speed leaving Sunset before coasting up the hill, the ascent will feel unusually slow.

And…. I think that about covers the basics. Really the biggest (only?) takeaway message from this for TriMet passengers is don’t ever touch the overhead wires since knowing the rest of this stuff isn’t a prerequisite for riding the trains but staying away from the catenary wires is just a good idea! But as always, I think the intricacies of the system and all of the things that go into making it work are fascinating, even if most people don’t care/don’t need to care about them.

Improved pedestrian crossing

I like this:

Pedestrian crossing on the east side of the Elmonica/170th platform

Don’t linger between the tracks!

The Z-crossing railings on both sides of this walkway force people to face the direction of oncoming trains before crossing – this is a relatively recent addition at Elmonica and other platforms to improve the safety of the walkway there since the substation makes it a blind corner for both pedestrians and train operators. And the freshly painted “STOP HERE” (looks like they haven’t gotten to the side near the parking lot yet though) and “DON’T STAND HERE” are nice improvements as well.

Aerial view of a Burnside Z-crossing near E 176th Ave

Aerial view of Interstate Z-crossing near N Wygant St

Z-crossings have long been in use on Burnside and Interstate, but it’s only over the last few years that TriMet began channeling people into Z-crossings on platforms. While I wish it were simple enough that people would stop and look both ways before they walk onto railroad tracks, the plain truth is that many, if not most people don’t.

So anything done to accommodate and counteract poor decisions that people make around trains in order to prevent accidents is great news as far as I’m concerned.

I don’t have children in the school system in Portland, so I don’t know how much (if any?) time is spent teaching kids that hey, there are these pretty, shiny, fast-moving trains going through neighborhoods and school zones in the Portland area, so here’s  how to be safe around them because they are not toy trains. Believe me, few things are as heartbreaking to see from a train cab as a parent taking their small children by the hand and running in front of your moving train, or sometimes pushing a baby stroller in front of an oncoming train.  Aside from the obvious risk involved, what is that teaching those kids? Nothing good – I can’t begin to tell you the number of times I’ve seen youths trespassing in the right of way, crossing where there is no pedestrian access, walking around in the tracks near platforms, running in front of oncoming trains so they don’t miss it, etc. But sadly there are plenty of adults who do all of these things too, so who is their good role model?

I think events like this one should be standard and ongoing for kids in Portland so that Portlanders learn from a young age how to be safe around the trains and rail safety becomes part of the safety culture in Portland, not just at TriMet.

ATU 757 and TriMet final contract offers

I don’t have time to write much right now, but for those wondering

What were the final contract offers by TriMet and the union that are going to arbitration?

Here you go – and many thanks to the person who provided this to me since I hadn’t been able to find any news outlet that posted the documents.

The first three pages are the union’s final offer (essentially, maintain the status quo and continue the previous union contract).  The remainder is TriMet’s final offer, which I have only had time to skim and so won’t comment on it, but it has a lot of line-item editing of the original union contract.

Hand signals

I’ve been looking at videos of the Shinkansen (the Japanese Bullet Train) on Youtube. I’ve never been to Japan, but if I ever get the opportunity to go, you can bet I will make it a point to ride the Shinkansen. More than once!

If you watch the videos, you’ll see the operator pointing at a lot of things. I think the pointing is fascinating – as best as I can tell, they’re trained to point at signals and speed signs. I wonder what the reasoning is behind that – to keep them from going on autopilot?  To ensure that they know where the signals and signs are? So that they can’t use “I didn’t see it” as an excuse if something happens?

It’d be interesting if they tried to implement something like this at TriMet.  I don’t think it’s necessary (we have the ATS magnets which will stop the train if an operator tries to go past an ABS signal that doesn’t have an indication to proceed). But it’s an interesting approach to staying alert – I know during training, new operators will be quizzed while operating (“What was the aspect of the signal you just passed? So what will the next signal be? Will there be another signal between you and the next platform?” etc) that help the students learn where to watch for signals on the alignment, and some students will continue to talk through those locations as they learn. But beyond that, there’s nothing like the pointing at signs or signals like the Shinkansen operators do.

MAX Hand Signals

MAX light rail hand signalsKind of looks like instructions for a line dance arranged this way.  Try this at the next wedding you go to.

MAX operators follow hand signals, but unlike the Shinkansen operators, don’t really give them while operating (and a friendly wave to the operators of trains or buses you pass doesn’t count).  Rail hand signals are one of the first things that operators are trained to do – by the end of day one we could all demonstrate & understand the hand signals for stop, stop at a particular spot, proceed, reduce speed, proceed AT a reduced speed, and back up.  And we learned how to acknowledge those signals from inside the train to let the signaler know we understood.  For the most part as a passenger, you probably won’t notice anyone giving hand signals to the train that you’re on, though sometimes you’ll be able to see workers in the right of way giving a proceed sign (“while facing the operator, raise and lower the arm vertically alongside the body”) to a train.

One of my first experiences with hand signals outside of the classroom (not counting workers in the right of way telling me to proceed) was on my last trip of my last day of line training – Control called my train to inform me that there had just been a car accident not far past a few platforms ahead of where I was. A car had crossed into the right of way and was stuck inches from the westbound track, and I was going to be the first westbound train through there, so I had to call Control for further instructions before leaving the platform closest to the accident.  My line trainer said he was comfortable letting me handle this if I wanted but he’d take over if I didn’t feel up to it.  I told him I wanted to do it, so when I got to that platform (and called Control telling them that I was there!), I left at walking speed and stopped where a supervisor on the ground told me to. Then I proceeded very slowly on his signal, reducing my speed even further as directed via hand signals while another supervisor checked alongside my train by the car to make sure there was clearance for me to keep going. There was *just* enough room for my train to pass without making contact with the car at that slow speed – the natural sideways sway of the train at full speed would’ve probably hit the car.

I had been running several minutes late (due to a mistake on my part when I had been westbound at Rose Quarter, I timed my calling my signal wrong and it timed out back to a red before I got my doors closed) and I was far too new to be able to make up for that lost time and get back on schedule – in fact I think I fell even further behind schedule. In retrospect I’m glad I was late, because if I was on time, that car might’ve crashed into me had I been going through that part of the alignment at the full speed.

Upcoming posts – more in-depth descriptions of the train cars, the overhead catenary systems, and a list of questions from one of the readers here.  So that should keep me busy for a while!