What are good points and bad points. Why TGV are built in locomotive-pull style. On the other hand, the Japanese bullet train are built in Electric Multiple Unit? and what kind of them do you think the most efficient?

The advantage of power cars (such as used in TGV, ICE 1 & 2) is that if there is a problem with the traction system it can easily be fixed through changing the power car, while the rest of the train is still operational. Some highspeed trains like railjet even use a modified locomotive for that purpose. In addition middle cars are lighter and can easily be disposed or even taken out for maintenance and other reasons. In terms of passenger comfort push-pull-style trainsets are usually better, as they tend to have less vibrations and noise stemming from the engines in the passenger section (just compare ICE1 and ICE3).

The advantage of EMUs is that traction is distributed all over the train, hence the traction power acts upon several axes all over the train, rather than just at the beginng and/or end of the train. As a result EMUs usually have better acceleration.

In the end both systems have pros and cons and it's hard to declare a winner in the game. Currently EMUs seem to have come into fashion over the past few years, but that doesn't have to say much.

Each concept has advantages / disadvantages:

TGV (TGV Atalntique, 485 seats, length 240 m, 300 km/h): The train has 8 traction motors. The power equipment is located in the two end cars.
Maintenance is easy since all the equipment is accessible from an aisle thru the machine room of the power head.
Max. axle load of the train: 17 t.

Shinkansen (N700, 1323 seats, length 404 m, Vmax: 300 km/h): The train has 56 traction motors.
The power equipment is distributed over the train. Traction equipment is placed under the floor or in cubicle near the entrance.
Maintenance is difficult since there are mor parts to be maintained which are located in areas with difficult access.
Max. axle load of the train: 10 t => less stress on tracks => higher speeds in curve

TGV has less parts and can be easier maintained, but stresses the tracks more.

If I'm not mistaken Shinkansens maximum axle load is at least 14 tonnes, the empty weight is slightly more than 10 tonnes per axle on the lightest cars... Anyways, Emu's are more efficient trains, I think locomotives will soon be obsolete in terms of passenger travel.

If I'm not mistaken Shinkansens maximum axle load is at least 14 tonnes, the empty weight is slightly more than 10 tonnes per axle on the lightest cars... Anyways, Emu's are more efficient trains, I think locomotives will soon be obsolete in terms of passenger travel.

I seriously doubt that. The majority of all trains are still classic push-pull-trains and it will take several decades to replace all that.

EMUs also tend to be more efficient when it comes to seats, since they don't have seatless powercars.

The main reason why the TGV has powered motor cars is the articulated design of the passenger cars that was chosen for the following reasons:
- less bogies, reducing the weight
- a lower body for better access at low platforms.
- no seats above the bogies, increasing the comfort.

Another reason for the power cars was the use of body mounted traction motors instead of bogie mounted traction motors. This is already difficult in non articulated EMUs so it was impossible to build those in the passenger cars of the TGV.
The Shinkansen 0 had much less design restrictions, using the much bigger loading gauge and only for use on the purpose build high speed tracks it they could go with an EMU design making it very light.

EMUs also tend to be more efficient when it comes to seats, since they don't have seatless powercars.


This argument is silly, as most modern highspeed trains are composed of so called half-trains with 7 passenger cars + traction (in case of push-pull trains). So there is no difference in that regard. In contrast, classic push-pull trains (loco + cars) tend to be much longer than single EMUs (which are often used in double traction on busy routes).

In terms of passenger comfort push-pull-style trainsets are usually better, as they tend to have less vibrations and noise stemming from the engines in the passenger section (just compare ICE1 and ICE3).


I've rarely felt anything but silky smooth acceleration on a Shinkansen.

I have felt vibration on French intercity trains though.

I can't speak for ICE3 vs. ICE1, but it would seem to me that vibration is more a matter of how the train is built and track qualtiy than EMU vs. Locomotive. However, this is purely anecdotal evidence from the recesses of a hazy memory.

The successor to the TGV, the AGV, is I believe, also an EMU design.

^^ The AGV is an articulated EMU with powered articulated bogies.

This argument is silly, as most modern highspeed trains are composed of so called half-trains with 7 passenger cars + traction (in case of push-pull trains). So there is no difference in that regard. In contrast, classic push-pull trains (loco + cars) tend to be much longer than single EMUs (which are often used in double traction on busy routes).
As silly as it is, it's used as an actual argument since it's given as one of the advantages of the AGV over the TGV.

And to be honest, I think it's a valid argument.

look

ICE 2 vs. ICE 3

half-train vs. EMU

391 seats vs. 460

That's 70 seats more in the ICE 3 trains that has the same length of 200 meters but a seat capacity that's 18% higher.

Eurotrain: ICE2 power car + TGV Duplex Cars = the beauty of push-pull systems

http://www.hochgeschwindigkeitszuege.com/germany/eurotrain2_gr.jpg

^^ And the best thing about it was that the Taiwanese Railways bought Shinkansen EMU's even after the Eurotrain was declared the preferred bidder.

http://i44.tinypic.com/99mcyb.jpg

And if Alstom can build the double deck AGV it will be the death of push-pull high speed trains. Then France can also buy it's High Speed EMUs just like Japan, Germany, China and Russia just to name some countries.

I hope you all realize that one of the biggest motivations of building multiple-units (I hope you will all stop using EMU as the universal word for multiple-powered trains, because there are diesel versions as well) is that it is much harder to build one extremely powerful engine as opposed to building a number of smaller less powerful ones.

There are many very true adventages to the push/pull system. Some of the the most important are the flexibility presented by the abilities to freely couple/de-couple wagons and the abilities to replace broken down engines. Where as to change the number of cars coupled to a multiple-unit will require a complete reprograming of the train's systems. For example, if you have an 8 car train but the demand calls for 2 extra cars, you will not beable to couple two more coaches onto the existing 8 car unit. To satisfy demand, you will most likely have to couple another full 8 unit train set and run the train with 6 units empty. Although the possibility of coupling two full sets of multiple-units together always exist, but it still doesn't provide the economic effeciency of adding or subtracting only one of two wagons at a time depending on need.

Also, multiple units have much more moving parts and as logic assumes, require more maintinence and have a greater chance of breaking down.


China went multiple units because it failed, after years of trying and many prototypes built, to successfully construct a single populsion push/pull high speed train system capable of meeting the required standards to prerform full-scale operational service.




This is one of the prototypes

http://upload.wikimedia.org/wikipedia/commons/5/5c/China_Star.jpg

^^ Everyone knows there are diesel versions, they're referred to as DMU's. The OP compared Shinkansen (electric) with TGV (electric) so that's why most people started referring to EMU's rather than bringing diesel into the equation.

The majority of passenger rail in developed countries (outside of North America and the UK) is handled by electric trains rather than diesel.

Although some might have caught the debate in another thread between myself and another member (with idiotic claims that TGV is an EMU).
It's really simple push-pulls are less costly in both initial and maintenace and replacement is alot simpler than EMU when the is a malfunction to a motor.
On the other hand EMU have a lower acceleration rates and higher maximum axle load on a single axle(loco axle) making construction cost a bit higher for tracks.

As for efficiency, as rule of thumb, with more electronic circuitry the greater the loss in power input due to resistance.

In my opinion...I think power cars are cheaper to manitan in long run and it's more simpler, but doesn't do as well as EMU at high speeds, but I could be wrong. I think EMU is "disposable" type of trains which if you want to use a duplex railcars, you can't do that with a EMU.

I like the new AGV which is a EMU which will top around 220 mph. I think EMU is the future, but I was amazed how many traction motors a EMU would have compared to the power cars. :)

In my opinion...I think power cars are cheaper to manitan in long run and it's more simpler, but doesn't do as well as EMU at high speeds, but I could be wrong. I think EMU is "disposable" type of trains which if you want to use a duplex railcars, you can't do that with a EMU.

I like the new AGV which is a EMU which will top around 220 mph. I think EMU is the future, but I was amazed how many traction motors a EMU would have compared to the power cars. :)

Actually less motors equate to faster speed because there is less magnetic resistance.
An electric motor creates a magnetic drag, with more motors there is more drag making loco with the same power output faster.

From what I read on this thread, they say that EMU is slower to accelerate than a power car pulling/pushing the railcars.

From what I read on this thread, they say that EMU is slower to accelerate than a power car pulling/pushing the railcars.

It's the otherway around.
Less axle load per powered axle means larger power band with less possibility of powerslips between steel track and wheel.

The train with fastest acceleration rate is the Shinkansen N700 series which most of it's axles are powered.

It's the otherway around.
Less axle load per powered axle means larger power band with less possibility of powerslips between steel track and wheel.

The train with fastest acceleration rate is the Shinkansen N700 series which most of it's axles are powered.

Makes sense... What's the acceleration rate of the Shinkansen N700?

The average diesel commuter train here in the US has acceleration rate of around 1.6 miles per hour per sec.

Makes sense... What's the acceleration rate of the Shinkansen N700?

The average diesel commuter train here in the US has acceleration rate of around 1.6 miles per hour per sec.

2.6km/h/s (commercial acceleration rate not necessarily the maximum accerleration rate)

2.6km/h/s (commercial acceleration rate not necessarily the maximum accerleration rate) Ah, that's similar to the diesel commuter rail trains, probably at full throttle but not at full throttle with that EMU HST.

Saying that the N700 is the fastest accelerating train is a bit wrong, since there are commuter trains in Japan (like on the Yamanote line) that have acceleration figures that are over 3 km/h/s.

It should be that the N700 have the fastest accelerating HST.

edit: posted in the wrong topic...

N700 has according to technical data (http://www.h2.dion.ne.jp/~dajf/byunbyun/tech/n700.htm) 2.6 km/h/s.
In Switzerland we go for commuter trains and tramways upto 3.6 km/h/s. Higher you can not go in commercial service since it would be unconfortable for the passengers and there is a risk that standing passengers fall over.

It would be funny when passengers fly then splat into the back of the train when it accelerates pretty fast.

I saw a video of a guy driving the Link light rail in Seattle, he was flooring it to the max and it was flying on the tracks! There wasn't any passengers, of course.

N700 has according to technical data (http://www.h2.dion.ne.jp/~dajf/byunbyun/tech/n700.htm) 2.6 km/h/s.
In Switzerland we go for commuter trains and tramways upto 3.6 km/h/s. Higher you can not go in commercial service since it would be unconfortable for the passengers and there is a risk that standing passengers fall over.

So that takes roughly 27 seconds to reach 60 mph at 2.2 mph/sec. I read somewhere that the Salt Lake city light rail can accelerate from zero to 55 mph in 21 seconds.

One important difference between push-pull trains and EMUs is that, if you change the
length of the consist, for a push pull train the power/weight ratio will vary, while with
EMUs it will remain constant. Add cars to a push-pull train and you will see lower
performance; add units to an EMU train and the performance will remain the same. This
is specially important if you have to adhere to a schedule that repeats itself for example
every hour of the day; replacing EMUs by loco-hauled trains in the peak hours to obtain
more capacity results usually in less performance and therefore delays.

One important difference between push-pull trains and EMUs is that, if you change the
length of the consist, for a push pull train the power/weight ratio will vary, while with
EMUs it will remain constant. Add cars to a push-pull train and you will see lower
performance; add units to an EMU train and the performance will remain the same. This
is specially important if you have to adhere to a schedule that repeats itself for example
every hour of the day; replacing EMUs by loco-hauled trains in the peak hours to obtain
more capacity results usually in less performance and therefore delays.


again. your theory works, but most EMUs do not allow flexible additions or subtractions from the set configuration. To make a 8 unit train 9 units will require almost a complete reprograming of the train's systems, which cost tons of money and takes lots of time.

You can only add EMUs by train sets, ie. you can hook up two 8 units sets. but you can't eaily add units, ie. add 2 more coaches to a 8 car EMU 10 cars. .

again. your theory works, but most EMUs do not allow flexible additions or subtractions from the set configuration. To make a 8 unit train 9 units will require almost a complete reprograming of the train's systems, which cost tons of money and takes lots of time.

You can only add EMUs by train sets, ie. you can hook up two 8 units sets. but you can't eaily add units, ie. add 2 more coaches to a 8 car EMU 10 cars. .

Of course ! That is not what I meant. But it is very unusual to have EMUs
that long. Most of the time EMUs are 2, 3 or 4 cars long. In that case, varying
the length of the train by adding one or more units is a very affordable
operation.

And for the case of the high speed trains, even those that resemble the most
to a loco-hauled formation, like for example DB ICE1 or ICE2, do not see their
consist modified so often. Once they are formed they mostly remain
untouched till their next maintenance. We'll see how ÖBB operate their
new railjets.

Of course ! That is not what I meant. But it is very unusual to have EMUs
that long. Most of the time EMUs are 2, 3 or 4 cars long. In that case, varying
the length of the train by adding one or more units is a very affordable
operation.


Huhhhh?
Where did you get that notion?
All EMU HSTs are 8 cart or 15 cart per train sets around the world.
Most metros are more than 8 cart per train sets and some are as long as 15 cart per set here in Japan.

Some HST EMU in Spain and Slovenian's ETR 310 (most of them are Pendolini) have 3 or 4 car and can work in multiple. Some mainline DMU in the UK have 4 or 5 cars.

But for new trains the standard is 200 m, with ability to run in multiple (like the Velaro, the NewPendolino, ...).

ICE 3: 8 cars
ICE T: 5/7 cars

However it has to be pointed out that EMUs are far more common in regional/suburban transit and less in long distance transit, where classic push-pull trains are still strong.

Huhhhh?
Where did you get that notion?
All EMU HSTs are 8 cart or 15 cart per train sets around the world.
Most metros are more than 8 cart per train sets and some are as long as 15 cart per set here in Japan.

Here in China, CRH2B and CRH2E EMU trains have 16 cars.

Passenger Capacity:
* CRH2B: 1230 (first-class seats+second-class seats)
* CRH2E: 520 (110 second-class seats, 410 sleepers)

I think Tri-ring meant 16.

The point is that EMUs aren't limited to 2, 3, or 4 cars.

Would be interesting to see a bi-level EMU HST with 32 cars (16x2) That's a lot of passengers for sure! Of course, the platforms would be too long for sure.

^ They are running 8 and 12 car long bi-level HST trains in Japan, and in some cases for extra capacity they even run 8x2 cars (this adds up to about 1600 passengers/train). But they can't go over 16 cars since the Shinkansen system isn't dimensioned to handle longer trains.

32 cars are about 800 m..........

32 unit passanger train? Where? Please show me.

^ They are running 8 and 12 car long bi-level HST trains in Japan, and in some cases for extra capacity they even run 8x2 cars (this adds up to about 1600 passengers/train). But they can't go over 16 cars since the Shinkansen system isn't dimensioned to handle longer trains.

Yeah, that's a lot of passengers in one trainset. I think u were talking about the Shinkansen MAX E4. The older version is the E1 which holds up to 1200 or so passengers with 12 cars.

again. your theory works, but most EMUs do not allow flexible additions or subtractions from the set configuration. To make a 8 unit train 9 units will require almost a complete reprograming of the train's systems, which cost tons of money and takes lots of time.

You can only add EMUs by train sets, ie. you can hook up two 8 units sets. but you can't eaily add units, ie. add 2 more coaches to a 8 car EMU 10 cars. .

I think you're confusing the usages of "unit" vs "carriage" in this thread.

An EMU/DMU unit would refer to the set of carriages that could not easily be reconfigured without a trip back to a workshop. There's no HSR in Australia but the regional rail services are operated using 2- and 3- carriage DMUs which allow any configuration from two to eight carriages, platform length permitting.

We also have a fleet of single carriage railcars which function as DMUs and can be hooked up to whatever length required. This can be contrasted with the older loco-hauled fleet where the carriages are grouped up into sets between three and six carriages long but typically aren't divided anyway.

Suburban EMUs here contain an unpowered carriage sandwiched between two powered carriages for those seeking a smoother and quieter ride.

I think you're confusing the usages of "unit" vs "carriage" in this thread.

An EMU/DMU unit would refer to the set of carriages that could not easily be reconfigured without a trip back to a workshop. There's no HSR in Australia but the regional rail services are operated using 2- and 3- carriage DMUs which allow any configuration from two to eight carriages, platform length permitting.

We also have a fleet of single carriage railcars which function as DMUs and can be hooked up to whatever length required. This can be contrasted with the older loco-hauled fleet where the carriages are grouped up into sets between three and six carriages long but typically aren't divided anyway.

Suburban EMUs here contain an unpowered carriage sandwiched between two powered carriages for those seeking a smoother and quieter ride.

To me, an EMU is measured in sets. A carriage is a unit within a set.

That is the correct analogy in my world.

Where a M car is a movement unit, and a T car is a trailor unit.

The main disadvantage of a loco-hauled HST is that the carriages are in great stres from the pull of the front loco combined with the push of the back loco

Also, wheelslip is more of a problem with a locomotive, especially in rainy conditions.

With Talgo Technology, is it correct to say that this will have to be loco push-pull?

The single axle bogies of Talgo cars cannot be powered yet, so you need a separate traction unit for the train to run. But this doesn't necessarily need to be a locomotive, Talgo is developing an EMU right now that has motor cars with passengers. Only the end cars that don't have the trademark Talgo single axle bogies are powered but it will be a completely articulated design making it an real EMU.

Info from the Spanish Train manufacturing thread:
Thanks Solchante, but I think Joseph1951 wanted to know about new news, nothing about what is already known

http://img718.imageshack.us/img718/7171/avrilf.jpg (http://img718.imageshack.us/i/avrilf.jpg/)

Eurotrain: ICE2 power car + TGV Duplex Cars = the beauty of push-pull systems

http://www.hochgeschwindigkeitszuege.com/germany/eurotrain2_gr.jpg

I have never see that before. :nuts:

Which speed is this train ?
Where this train functionned ?

Thanks. :)

While it's not a high speed train, the Dutch double decker VIRM EMU's are easily exchangable, for as far as I know.

Originally, they were delivered as sets of 3 or 4 units. Later on, they were extended to form sets of 4 or 6 units. Units are easily exchanged, for example, during maintenance.

The longest allowed combination is 14 units, which consists of 1 train of 6 units, and 2 trains of 4 units each. This gets you a train length of roughly 400 meters, most platforms in The Netherlands are shorter than that so this combination is unlikely to happen.

If this 14 unit train would be completely full, with every seat and spot taken, it would carry 2057 passengers - staff not included.

I have never see that before. :nuts:

Which speed is this train ?
Where this train functionned ?

Thanks. :)

This was the "eurotrain", a joint bid by GEC-Alsthom and Siemens for the Taiwan high speed rail project. One set was formed only, it never ran revenue service, and doesn't exist anymore.

Furthermore, it's a pair of ICE-1 (or was it ICE-2? I forget) powercars coupled to a TGV Duplex carset. Which is why it looks (IMO) rather ugly. You can also see that it was demonstrated in (or near) Germany, as there's an older ICE trainset in the usual ICE livery in the background.

The new KTX-II units being built by Rotem are largely based of traditional TGV tech, as the (Alstom) TGV Atlantique model is the KTX-I. Alstom, I'm sure, is currently developing an AGV Duplex model.