Hi there. Lots to cover this week. Namely, our newly released L service schedule through March 2020. Spoiler: we were able to cut back a few of the weekend outages. Check it out.
Also, why exactly do we need to shut down L service for a full weekend? Our Chief Electrical Engineer hosts us for an energizing debate. Have a pleasant, spring-like weekend.
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Don't let the gray appearance fool you. Powerful stuff happens here—it's the new substation near Avenue B, one of three substations for the L Project. This is where we take Con Ed power and convert it into power that can run more L trains.
Photo: Trent Reeves / MTA Capital Construction / December 7, 2019
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More power to you! How we're electrifying the L
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As announced, we'll be shutting down both L tracks in the tunnel for the March 20-22 weekend so we can hook up power lines to our new substations. Why? And how does it work?
We sat down with Stan Karoly, Chief Electrical Engineer at MTA New York City Transit, to find out more about these electrifying developments.
L Project Weekly: Just want to verify one thing. We built the new substations to deliver more electrical power to the L line. And more power means we can run more trains, right?
Stan Karoly: That's correct. With its modern signaling already in place, we can run trains more frequently. And the L warrants an increase in service. But for more trains, we also need more power.
LPW: So let's talk about how our power system works. Where does it come from?
SK: We get our incoming substation power from Con Ed. We used to make our own power, but that's a story for another day. It comes up at "medium voltage," which could be any number of voltages in that range. So it could be 13,200 volts to 33,000 volts, depending on what's available in that area.
LPW: And that goes right to our tracks?
SK: Actually, no, but this is the perfect set up to talk substations. The Con Ed power first needs to be converted from high voltage AC, to lower voltage AC, then to DC power. That happens at the substations by taking the high voltage power and connecting it to a step-down transformer. We convert it to 650 volts DC, which then can go right to the third-rail.
LPW: So we take high voltage and make it low voltage for the tracks?
SK: Yes, our track power is in the 650 voltage range. We also get lower voltages like 120/208 voltage, too, but that's what we use for things like tunnel lighting.
LPW: This may be a dumb question, but how do we know how much power we need? In other words, how do we know how much power to ask Con Ed for?
SK: This is actually the first step in the process, even before a shovel hits the ground of a future substation site. We do what we call a "traction power study." Lots of factors are considered. We look at trains-per-hour max, what the signaling system is, availability of the cabling system to carry the actual power. We get input from Maintenance of Way (MOW) Engineering, Power Operations, Operations Planning, and others. The max power we can get per unit from Con Ed is 3 megawatts. Most substations are two unit substations, so the total power available is 6 megawatts.
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LPW: So why do we have to shut down service to hook up the power?
SK: Cables have to be physically connected to the tracks. That can't be done safely if the track is live! So power is removed in the affected section and obviously, no trains can then run. The traction power system is an integrated ecosystem, and you can't separate it track by track. Positive cables go to the third rail and negative cables feed to the substation. It's a delicate loop, and there are lots of things that need to be in place before we can connect the loop. Right now for example, at the two Brooklyn substations, we have all of our 2000 MCM cables (MCM is an abbreviation for "thousands of circular mils," a measurement of wire gauge) spliced with 500 MCM cables, which then will connect to the tracks once we're ready.
LPW: Um that's a lot...so our takeaway here should be "safety first"?
SK: Always! I know electrical jargon can get complicated. But I hope this shows just how many steps and factors there are, including safety for you and us. Lots of planning goes into this. We don't just take trains out of service on a whim. For this work, there's just no other way.
LPW: And what will be doing over this March weekend?
SK: Two things. At the substation near Avenue B, the team will be connecting negative and positive feeder cables from the substation to the circuit breaker house for both sides of L tracks. At the ones near Maspeth Avenue and Harrison Place in Brooklyn, they'll be connecting power cables from the substations to the tracks.
Quick fun fact that's relevant here: if the distance between the third rail and the substation is greater than 300 feet, we build a circuit breaker house. It acts as an intermediary between the third rail and the substation. That's what we had to do for the substation near Avenue B, but the ones in Brooklyn connect right to the third rail.
LPW: Sounds like you're charging right ahead! Thanks, Stan, and to the whole team working on this electric initiative.
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Service news recap: Mark your calendars 📅
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We're making progress, and that means we can lock in those weekend dates with no L service in certain areas. Check out the full press release with the rundown of all the work we're doing, including the steps to connect power to our three new substations, and save these dates:
Jan 17-20 weekend: No L service in Brooklyn between Lorimer St and Broadway Junction.
Feb 14-18 weekend (Presidents' Day included): No L service in Brooklyn between Lorimer St and Broadway Junction.
Mar 20-23 weekend: No L service from 8 Av to Broadway Junction.
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What you should know about upcoming service changes if you're really into knowing very detailed information
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 Before we started the tunnel rehab in April, one Community Board 1, Brooklyn, resident spoke up at a meeting and said, "We need more detailed updates about service changes! All of it!"
That moment stuck with us. So in honor of that vocal, info-loving resident and our obsession with explaining things about subway service that you don't really need to know but will make you a more informed customer, here you go:
G, weeknights, Jan. 13-17, midnight to 1:30 a.m.: As we mentioned in last week's issue, we have overnight emergency work to do on the G. This means G trains will still run, but those extra trains won't operate between midnight and 1:30 a.m. these weeknights. Also FYI: if you're at Greenpoint Av Station, no matter which direction you're going, trains will stop on the Court Square-bound platform.
L, weeknight, Tuesday, Jan. 14: This week is L-monthly-track-inspection week! Tuesday night, service will be closer to normal as we will be running L trains on two tracks, and doing inspections between trains (what we call "working under flagging"). So service will be a little less frequent, but definitely more than every-20-minutes.
L, overnight at Bedford Av Station, Friday, Jan. 17, 11 p.m. through 5 a.m.: Come to the station with your fare ready! We're connecting new fare control machines and that means overnight, we have to temporarily disconnect power to all the fare control machines and about half of the turnstiles. We're working to have the MetroCard van there, but we'd recommend coming ready to swipe.
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Glamour shot of the week: Maybe not the coziest bed, but it's certainly clean
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"Track bed" that is. We're on pace to finish the rest of it, along with all the appropriate new tracks, ties and other equipment, in the Q1 tube this weekend.
Photo: Trent Reeves / MTA Capital Construction / January 5, 2020
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Construction look-ahead: Week of 1/11/2020
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We're on the home stretch for the track work. And we're progressing the FRP panel installation, new conduits and cabling, among other items. Here are the highlights of what we're doing in the week ahead:
- Continue installing the structural FRP panels in one work zone
- Make steel repairs at Bedford Av
- Continue installing conduit and wire to power transponders, the fire alarm systems at Bedford Av and 1 Av, and fare control machines and speakers at Bedford Av
- Test and terminate communications cables
- At the Avenue B substation, install control and communication wires, wire the circuit breaker house and install brackets and cleat 2mil cables
- Install the negative equalizer in four zones
- Install new contact rail and weld negative rail in two areas
- Continue energy-efficient tunnel lighting installation: install tunnel lighting brackets and strapping cables at N 7th St
- Install more discharge pipe and manifolds from N 7th St to the pump room
- Unload and move into place new elevator equipment for Bedford Av
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