Railroad Forums 

  • Electric Units and bi-level cars

  • General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.
General discussion of passenger rail systems not otherwise covered in the specific forums in this category, including high speed rail.

Moderators: mtuandrew, gprimr1

 #111313  by rrail373
 
So far I haven't seen any pictures of electric units pulling or pushing bi-level passenger cars, only single-level cars (ex: Acela). Is it considered impractical or inefficient to conduct such an operation?

I'm wondering, because, say a commuter rail system dependent on diesel units wanted to electrify its tracks, could they just purchase new electric units to pull/push their existing gallery/bi-level cars? Or would such an agency be better off just purchasing new single-level cars, maybe even electric multiple units (single or bi-level) for speed/acceleration efficiencies?

Thanks in advance.

 #111351  by DutchRailnut
 
In Europe push-pull is done alot with Doble decker cars and electrics.
In Netherlands Push Pull is done with either locomotives or Double decker lookalike powercars were top level is passenger car the bottom level is locomotive.
The interesting wheel arangement on power car has B-B-B for wheel arangement to get more traction on rail.

http://www.christrains.com/nsddar.html

 #111726  by Irish Chieftain
 
You sure you're talking about HSR here?

To bring things back on-topic, there's the TGV Duplex, which have been running for about a decade now. There are also bilevel trailers on Shinkansen 100-series cars...

 #111925  by wigwagfan
 
Why not employ third-rail power distribution?

As long as all of the platforms are on one side of the track so that the third rail can be placed on the other side.

 #111973  by DutchRailnut
 
Third rail power is not high speed, best speeds on third rail with regular trains is about 80 MPH, High speed rail is basicly anything over 125Mph.

 #112447  by metrarider
 
In the UK, trains powered by 3rd rail reach 100mph, and the Eurostar uses 3rd rail for it's low speed portion of UK running. (the new dedicated line is all 25kv catenary)

There is no reason why Catenary cannot be used with bilevel equipment, but you don't see it much in the States because the clearances on the NEC make it difficult to design a bilevel that fits under the wire and the low clearance tunnels present.

3rd rail generally is fine for rapid transit systems, subways, etc, but for heavy rail, having high voltage overhead wire is much more efficient in that it costs less to deploy, has much lower line loss, requires fewer substations, can use utility voltages directly, provides more power, and is up and out of the way were people (hopefully) will not be subject to electrocution should they be on the track for legitamate or illegitimate reasons.

RE:

 #112638  by rrail373
 
Thanks for all the insight. I've learned quite a lot in this thread alone.

Metrarider - it seems that METRA uses both diesel locomotives and electric multiple units. I'm just wondering, say METRA decided to use electric units, (w/ pantograph) like they use on the NEC, to push or pull METRA's existing Nippon Sharyo gallery cars. I'd think such a train would have poorer acceleration compared to an EMU set, but would that setup be considered costlier and inefficient compared to just using EMUs? Would a commuter rail agency that has launched an electrification project (w/ a new overhead catenary) be wise to purchase EMUs rather than to have electric units power its existing passenger cars? Thanks in advance.

 #112687  by Irish Chieftain
 
wigwagfan wrote:Why not employ third-rail power distribution?
Hmm...a substation every 20 miles with 25kV 60Hz AC catenary wire, versus a substation every 2 miles with DC third-rail...plus gaps at switches and crossovers...never mind the aforementioned other issues...
As long as all of the platforms are on one side of the track so that the third rail can be placed on the other side.
Is this assuming low platforms?

And there aren't too many tracks that have platforms on both sides of them (Jamaica NY comes to mind, as well as some subway stations on NYCTA)...

For rrail: Here's the Metra forum and the commuter rail general discussion forum. I hate repeating myself, but...this is the high-speed rail forum and you have a bunch of questions not related to high-speed rail whatsoever.

 #112728  by Nasadowsk
 
<i>There is no reason why Catenary cannot be used with bilevel equipment, but you don't see it much in the States because the clearances on the NEC make it difficult to design a bilevel that fits under the wire and the low clearance tunnels present. </i>

Interesting.

The LIRR runs bilevels into NYP, and NJT will be soon, too.

MARC runs them between Baltimore and DC....

Third rail isn't suited for HSR for lots of reasons, mostly contact related (100mph is the realistic max speed), and supply issues. Basically, Ohm's law kills it...

 #132916  by drewh
 
And there aren't too many tracks that have platforms on both sides of them
PATH NWK and Pavonia come to mind.

 #132941  by Nasadowsk
 
A few places on the LIRR, do too:

Hicksville
Floral Park
Jamacia
Penn
Lynbrook, or I think Valley Stream or RVC.
Ronkonkoma
Babylon

I think there's a few more, too.

Then ther'es places where the third rail runs under the platform, anyway.

Realize, prior to the M-1s, the LIRR had *low* platforms, and a number of stations where the third rail was on the platform side.

Anyway, yes, there are electrically haulled bilevels, yes, there are even EMU ones, and not surprisingly, yes, there are high speed ones. Japan has a few, France has a few.

 #132956  by drewh
 
Realize, prior to the M-1s, the LIRR had *low* platforms, and a number of stations where the third rail was on the platform side.
Seems pretty unsafe ... where was this?? Any problems??

 #133453  by Nasadowsk
 
West Hempstead immediately springs to mind:

http://www.nycsubway.org/perl/show?10662


The third rail actually was below platform level, and the coverboard covered it.

Bizzare, but apparently they thought it was ok in the early 1900s....

I doubt this would pass by the regulators today....

 #133810  by hsr_fan
 
MARC runs these cars on the NEC every day. I believe the Kawasaki bilevels are rated for 125 mph operation.

 #143789  by David Cole
 
Just out of curiousity, does anybody know the height of the TGV Duplex cars? They look shorter than the Amtrak Superliners (16'-2"), possibly about the same height as the bilevel cars found on NJT (14'-6") or LIRR. I imagine they couldn't get much shorter than that, or else you'd have headroom issues inside the cars.

Would there be any technical reason why something as tall as the Superliners couldn't be run on high-speed lines (186+ MPH) other than weight and wind drag? I seem to remember reading somewhere that the height of the center of gravity is also a big factor, but I can't find it again.

(Edit: I've since learned that the Superliners actually have a lower center of gravity than the single-level Amfleet coaches. Interesting.)

Thanks...