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  • Why is 25 KV used for Hoboken and Coast Line?

  • Discussion related to New Jersey Transit rail and light rail operations.
Discussion related to New Jersey Transit rail and light rail operations.

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 #1356815  by Ken W2KB
 
jackintosh11 wrote:Couldn't they do 60Hz for WAS-Hell Gate?
Yes, but I suspect that the cost to replace the protection system relaying and modifications to the signal system, as well as costs for new substations and enhancements to electric utility transmission to supply single phase power is higher than simply expanding frequency conversion capacity such as is being done at Metuchen.
 #1356816  by Ken W2KB
 
Jeff Smith wrote:Admin Note: I clarified the title a bit.

Let's be clear; I think this got confused a couple posts ago. The topic originally concerned Voltage (kv) vs. Hertz (hz). Hertz is frequency.

If Ken could clear up the details, I'd be appreciative. I'm not an engineer (of train or any other kind), so don't ask me.

I do believe clearance on the New Haven line (specifically near Mt. Vernon) had something to do with the selection of 12.5 kv, but don't hold me to that, and also, that's Metro North, NOT New Jersey Transit, but as a point of reference, it's interesting. The switch to 60 Hertz I think had to do with commercial availability and the disrepair of the NH Cos Cob power facility. 60hz is the North American standard (vs. 50 I think in Europe).
You explained it correctly. :-)
 #1358222  by Jishnu
 
F-line to Dudley via Park wrote:Do they have any plans (or long-term desire?) to convert the last 25 Hz portion of the NJCL to 60 Hz/25 kV when they've got their frequency-agile next-gen EMU's ordered. A little bit weird to have their own phase break to maintain on a branchline.
The Arrow EMUs are frequency agile. Being capable of operating under 25Hz makes them able to operate under 60Hz. They are just not voltage agile because they don't have automatic transformer tap changers.

Single phase 25kV electrification fed from 3 phase commercial power feed by its very nature has many phase breaks to balance out the feed among the three phases.
 #1358261  by OportRailfan
 
jackintosh11 wrote:Couldn't they do 60Hz for WAS-Hell Gate?
That would relegate the six-25Hz frequency converter stations, which Amtrak has invested probably hundreds of millions, if not billions, of dollars in. Plus the signal system from GATE to WAS is based around the 100Hz/91.67Hz signal power, and 25Hz traction power framework. Again, it would cost vast sums to convert these systems to operate on commercially available 60-cycle.
 #1358262  by OportRailfan
 
Sidenote: The Coast Line is powered via Amtrak's 25Hz traction power from Union to the South Amboy sub. I believe the Aberdeen phase break is the division of 25Hz and 60Hz. Not sure about the signal power west of UNION/starting at GRAW

Double-sidenote: Catenary used to go all the way from ESSAY/SA Interlocking, all the way to MIDWAY. There is a defunct substation west of Brown's Yard in East Brunswick/Spotswood (Outcalt Substation (I wonder if Amtrak still owns this, or if it's Conrail's property)) on the Amboy Secondary. This sub was roughtly halfway down the line between SA and MIDWAY
 #1358538  by n2cbo
 
If memory serves me, I believe that once during a major derailment back in the 1970s on the NEC line in Metuchen, Amtrak ran some trains via the old C&A between Midway and Essay, over the NJCL to Union, then back to the NEC. I remember seeing GG1s operating there during the reroute.
 #1371015  by michaelk
 
When I was a boy, i lived in Matawan and "commuted" on weekends to visit my father in NYC and later Elizabeth. When I started it was NJ DOT and hodgepodge cars and diesel power with an engine change in South Amboy. Then they added the electrification to Matawan. Then later they added the Matawan to Red Bank and Red Bank to long branch sections.

my understanding/recollection of NJCL is that the extension from South Amboy to Matawan was/is an extension of Amtrak flavor power already from NEC to South Amboy. As Above there was enough "left over" in Amtraks system to handle that. I'm fairly certain that runs just past the Matawan (now Aberdeen) station and onto a set of siding tracks just path the station that dead end at the GSP bridge (IIRC = Natco branch?). That's all built with overhead wiring just like the rest of the Pennsy part of the NJCL and the NEC. Same sort of heave duty steel overhead towers- just painted baby blue instead of rusted.

After that first segment from South Amboy to Matawan was built- JCPL put up giant monopole transmission lines from their substation on Wilson Avenue in Aberdeen to service the line southbound out of Matawan. That transmission line actually runs along the old Matawan- Freehold ROW - then operated by conrail with service to imperial oil in Marlboro, and the lumber yard and brickyard at the intersection of Rt 79- now it's the Henry Hudson Trial- maybe in 100 years it will be part of MOM service. I grew up in a subdivision adjacent to that ROW- I remember the grownups losing their minds about the power lines being built. At the end of that transmission line, there's a substation of some sort inbetween to the natco branch, GSP, NJCL, and Lloyd Road in Aberdeen. I assume that's where the JCPL flavor gets converted to NJT flavor.
 #1401733  by michaelk
 
speculation i guess, but seems impossible to me that they would order otherwise. If they buy locomotives that do it why wouldn't they buy MU's that can do it? certainly any (reasonable) additional cost would be worth it for the flexibility it would afford them- no?
 #1401834  by R36 Combine Coach
 
TDowling wrote:will the arrow 4s be able to change voltage on the fly, assuming that they are ever introduced?
Not sure, but the Silverliner V might be already factory equipped (or ready to be adapted) for such.
 #1407456  by amtrakowitz
 
Slightly OT: As far as Europe goes, Germany, Austria, Norway, Sweden and Switzerland are excepted on their railroads, building even new electrification as 15 kV 16⅔ Hz—including in the Gotthard Base Tunnel.
TDowling wrote:Will the Arrow 4s be able to change voltage on the fly, assuming that they are ever introduced?
They were always touted, both by NJT and advocacy groups, as having such an ability. And it would be questionable if any EMU would come around at this point bearing the name "Arrow IV", what with the last design broached being that of a "MLV power car" (the push-pull MLVs, to which these "power cars" were supposed to have been mated, never bore the moniker "Comet VI" after all).
 #1407482  by F-line to Dudley via Park
 
It's actually now just "regular old MLV EMU", per the engineering specs contract they issued 2 years ago. They panned the power car idea as a little too big a reach years ago. These will be typical vanilla mated pairs or double-ended singlets that trainline with only each other...stuffed in the MLV carbody with MLV seating, and frequency-agile for changing on-the-fly between 25 Hz/12.5 kV, 60 Hz/12.5 kV, and 60 Hz/25 kV. Call 'em Arrow IV's wearing an MLV costume.

The specs contractor should've returned their handiwork to NJT by now. Whether there's anyone at the home office to actually read through it right now and report back to the board is the bigger issue with all the turmoil the agency is in and all the unfilled management positions. They're stuck in paralysis on all vehicle procurements, not just this one.
 #1407505  by Fan Railer
 
Which doesn't bode well, especially considering the woes Bombardier is going through at the moment as well. Not sure which other vendor NJT would turn to for the Arrow IVs at this point if Bombardier doesn't shape up.