Link Light Rail Credit: Lizz Giordano

Link Light Rail operators have been given orders to slow accelerations to reduce stress on the system after an electrical failure at the Tukwila International Boulevard Station substation Tuesday resulted in a power outage to the southern portion of the Link light rail system, according to Sound Transit.

On Tuesday a “major electrical substation failure” at the Tukwila Station suspended service between Othello and Angle Lake stations for approximately six hours. A bus bridge, which had as many as 36 shuttle buses running during its peak, transported riders until service resumed around 4:30 pm.

Earlier on Tuesday, trains were also stopped at the Mount Baker Station “after a unit along the trackway that sprays lubricant caught fire,” according to Kimberly Reason a spokesperson for Sound Transit.  The fire was quickly extinguished.

At this point, Sound Transit hasn’t been able to determine the cause for either service disruption on Tuesday.

While there is no obvious connection between the two events, “given the unusual nature of these events and the proximity of the lubrication unit to elements of the traction power system, we have not ruled it out,” Reason wrote in an email.

Sound Transit is also investigating if the substation failure at Tukwila is related to Sunday’s two-half hour outages at Angle Lake. But damage incurred during the Tukwila substation failure has complicated the investigation.

“Our diagnostic challenges are compounded by the fact that the Tukwila failure caused major damage to the breaker and control system, destroying wiring and all equipment with memory that might have provided information about the events leading up to the failure,” Reason wrote in an email.

According to Reason “service was restored after staff completed work to allow use of the Tukwila substation as a tie switch rather than as a power source, enabling power to be fed from other substations.”

Sound Transit said slow orders to operators will reduce voltage spikes and stress on the system and will continue as the investigation moves forward and permanent repairs are made.

Reason said the work underway includes consulting with both the electrical system designer and the equipment manufacturer. She said at this time it is unknown if the high temperatures played a role in the outages.

Addressing the Capital Committee Thursday, Peter Rogoff, Sound Transit CEO,  said orders to operators to slow accelerations was done as a precaution.

“These slow orders, fortunately, will have minimal to no impact customers and travel times,” Rogoff said. “Redundancy is going to be built into all of these systems, but most importantly we need to get to the root cause of this problem, especially if it was related to the Sunday outages which means we are having a pattern rather than a one off.”

20 Replies to “Drivers Ordered to Slow Acceleration Following Outages”

      1. Absolutely correct. Portland’s system was built with an eye to minimizing costs. That is why they ran on the surface through DT Portland (cheap, but slow and limits them to 2 car trains), why they ran 4 lines over the Steel Bridge (cheap, but slow and unreliable), and why their cantenary can’t take the heat (again, cheap, but unreliable on hot days).

        Seattle’s system was built to much higher standards with higher line ridership expected. It cost a lot more, but it should hold up better and support higher ridership.

        But don’t be too hard on Portland. It is hard to be first — you make all the mistakes and the person that follows after you benefits.

        That said, I wonder if we can blame Canada for at least the electric portion of these problems. I don’t know if they are using vacuum breakers, but all that smoke in the air must be changing the dialectic constant of air.

      2. The “dialectic constant”? Is even electrical engineering infested with Leftists these days? /snark

        Perhaps you meant “dielectric”?

        Damn that pesky auto-correct!

      3. MAX has constant tension catenary, just like Link.

        At temperatures above a certain point, the counterweights bottom out. You will have this problem on Link when Seattle gets this hot. Just give it another couple of decades of global warming.

      4. @Glen,

        Yes, Max has constant tension cantenary, but not just like Link. Portland intentionally designed their system to accommodate a smaller temperature range. It was an intentional design decision to save money during construction with the design mitigation being to slow the trains down on really hot days. It is just one of the design decisions they made to save costs.

        But MAX was designed to (on average) be a slower system with lower line capacity. They went for coverage over peak thru-put.

        Link is a bit of a different beast. Higher line capacity, higher average speed, and higher peak thru-put on the important screen-lines. Hence the term “Light Metro” that a few of the transit wonks occasionally try to attach to Link. What Link lacks (currently) is coverage.

        But we won’t really know if ST got it right until 2023 when Link ridership exceeds MAX ridership on a day-in-and-day-out basis.

  1. Does ST put specifications for an auxiliary power supply on its vehicles that allow for them to run 10-20 more miles? Do they make cars or cabs with alternate self-contained power like batteries or CNG that can be attached to a light rail train to move it?

    I’m no expert on these things, but not having equipment that can’t have some trains up and running within an hour or maybe two seems neglectful. It couldn’t be that hard! Power problems will occasionally occur and having an effective contingency plan seems obvious.

    1. Only several systems have light rail cars with built in battery systems. They are not available off the shelf.

      Even line side batteries are not common at all. However, even that would have issues if the substation is gone.

  2. Here’s hoping that its hot weather + particulates + 3rd car. Then you can write up a protocol to slow acceleration if the temp goes above x.

    Otherwise, now that it is uncovered, isn’t this the sort of thing that the testing phase for North and East Link should suss out?

    1. The transformers may have been under additional strain if they were serving any HVAC systems. It’s stunning that they don’t have the data needed to swiftly complete this investigation. It isn’t 1917: we can track this stuff with computers.

  3. This outage issue showed up in the most recent news roundup this week and I remarked then about its importance and the lack of discussion in the comment section.

    This is completely unacceptable. Looking at the higher than normal (for the PacNW) temps of late as well as the particulate matter drifting down from BC seems like a lot of scapegoating. How often have high temps led to sustained track power outages in San Diego or Phoenix? And now Rogoff speaks about building redundancy into the system. Really?

    Btw, so where did ST get these 36 so-called “bridge” shuttle buses on the fly? Anyone know how this all worked? Is there a contingency plan to reallocate temporarily as needed a whole bunch of idle Metro buses?

    1. Contingency procedures, yes, but unfortunately, Metro runs can be canceled when big-time bus bridges like this happen (they only have so many operators on the bench and coaches ready to go, particularly in peak periods). I believe the O&M agreement allows this to occur.

    2. As for places like Phoenix: they have the reverse problem in the winter when it gets too cold

    3. The bus bridge this time was provided mostly by Metro, but also by Pierce Transit. Pierce handled more “express” service between Othello and the airport. Meetup handled the local service for all stations.

      Metro called lots of operators who were finishing up their work for the day, as well as part time operators.

      Many part time operators hang out at the bases between morning and afternoon trippers, either to scrounge for work, or because the commute home doesn’t make sense. I was one of the many at the bases who heard the PA call for bus bridge operators and went out from 11:30a to 6:00p. Coordinators and dispatchers were able to fill my normal afternoon work with a report operator.

  4. I’m impressed that Metro managed to put 36 buses into service on short notice. Were these all spare buses and on-call drives, or were some pulled off other routes?

  5. Using Link in 2014 it often surprised me how hard they accelerate the train from a stop, if you were not sitting down or hanging onto something you’d fall over.

    Sounder on the other hand, has two engineers that handle this train perfectly +1 to them. Prompt and consistent acceleration to 80mph, and firm decelerations with a perfect stop into stations. The new guy has some catching up to do, hopefully no one gets brained on the stairs with their platform overshoots, backing up then a jarring stop.

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