Bombardier EDMU

[Geezertronic]

I wonder if the new coaches will be unpowered when not on OHLE? Or whether they can design functionality so that the new coaches are traction powered off the existing deisel engines when not on OHLE (if you get what I mean)?

 

[ailsa]

I would have thought they will stay the same. Whilst there are no longer hard and fast rules regarding numbering sequences (if there ever were ) 2xx sequence is for Diesel-Electric trains which the 22xs would remain.

Is this a possible use for the 6xx series of numbers?

Also the 73s (and 74s) were numbered as DC electric locos, despite the presence of a diesel engine, which would suggest that the 22Xs could just as well be numbered as EMUs as DEMUs?

 

[sprinterguy]

I wonder if the new coaches will be unpowered when not on OHLE? Or whether they can design functionality so that the new coaches are traction powered off the existing deisel engines when not on OHLE (if you get what I mean)?

Pantograph cars are generally unpowered in EMUs to keep axle loadings down, and of course there's more equipment to pack into an EMU pantograph car, so I would imagine that any Voyager panto cars will also be unpowered. Plus sharing out the electricity generating capability of the existing diesel engines to power a greater number of traction motors on the new carriages could, I reckon, be detrimental to the traction motor performance.

Does anyone know for sure if the pantograph cars will only be fitted to the 220 & 221 classes, or to the Meridians as well? I'm under the impression, through some of the calculations made previously, that it will only apply to the Voyager units. I think adding panto cars to the Meridians would only go ahead if further electrification of the MML was announced.

 

[philjo]

I would imagine that when switching from electric to diesel you would have to stop, as presumably the diesel engines will have to warm up for several minutes before they can reliably generate enough power to move off (unless the engines were started a few minutes before changeover whilst still running on the electric supply ?). e.g. at KX the HST engines appear to be started up about 15 minutes before departure time.

The big winners on existing OHLE routes would be the Euston-Chester/holyhead route (changeover at crewe) & XC services using ECML (changeover at York) plus of course Birmingham-Edinburgh/Glasgow services which are entirely under the wires.

 

[ainsworth74]

Install a short section of higher tension wire in the change-over zone?

Well that would seem to make sense, I certainly can't see any reason why that couldn't work. But then I'm not an OHLE engineer I was only mentioning what I've heard elsewhere.

Is this a possible use for the 6xx series of numbers?

Well I suppose it could be. But personally I still don't see any need for re-numbering, their current number would still seem to me to fit even if they were converted to include pantograph cars. Of course if they had their diesels removed (as some one suggested for the 222s) then they should be re-numbered in to the 3xx range. Otherwise I don't see a need.

 

[tbtc]

I'd imagine that if the 22x class used the same train management system, they too would have to stop.

I suppose one way round it would be to stop them all at Bedford and scrap all calls at Luton/ Luton Airport?

Out of interest, if the Panto-coaches were to be built, presumably this would be without engines, so would a seven car Voyager be able to run with only four engines?

 

[LE Greys]

I suppose one way round it would be to stop them all at Bedford and scrap all calls at Luton/ Luton Airport?

Out of interest, if the Panto-coaches were to be built, presumably this would be without engines, so would a seven car Voyager be able to run with only four engines?

A five-car Voyager can keep time on three, but I'd imagine that there would be two PTSOs and one MSO, so that's five out of seven. Either that, or there would just be two new vehicles, making six. I hope that one of them has a decent-sized buffet area.

 

[b0b]

The 22X's are not EMU's powered by diesel generators? For some reason I always thought thats how it worked.

 

[ainsworth74]

The 22X's are not EMU's powered by diesel generators? For some reason I always thought thats how it worked.

Everything I've read says that they have diesels engines powering generators which supply power to traction motors. So yes EMU's powered by diesels, hence why it should be fairly simple to convert them to run off the wires.

 

[LE Greys]

Everything I've read says that they have diesels engines powering generators which supply power to traction motors. So yes EMU's powered by diesels, hence why it should be fairly simple to convert them to run off the wires.

They changed this beastie from gas turbine to electric in 1958, so I should have thought that it should not be too difficult with modern technology.

 

[charlesn132]

No, 3xx is for EMUs

I would have thought they will stay the same. Whilst there are no longer hard and fast rules regarding numbering sequences (if there ever were ) 2xx sequence is for Diesel-Electric trains which the 22xs would remain.

Thanks, was just wondering because there are no ED multiple units and the class 73s are numbered as DC electric loco's I think

 

[MCR247]

But a DEMU is an EMU powered by diesel engines so they are fine there

 

[charlesn132]

But a DEMU is an EMU powered by diesel engines so they are fine there

That's why I asked

 

[The_Stig]

I would imagine that when switching from electric to diesel you would have to stop, as presumably the diesel engines will have to warm up for several minutes before they can reliably generate enough power to move off (unless the engines were started a few minutes before changeover whilst still running on the electric supply ?).

I would think that it could be possible. With the stock fitted with GPS it would be possible to start the engines 5 min's before the desired switch over points. Electric trains have sections when their VCB's are tripped and running on auxiliary supplies only. Simply switch the power from OHLE to the diesel motors at these (or similar) points?

 

[TheWalrus]

When you say pax wouldnt like an extra 5mins, would that be for the add call at Bedford, or just to switch from one to the other?

 

[MCR247]

The call at Bedford to switch over if it can't be done on the move, although it would probably actually add around 10 - 12 minutes.

Anyway, the wires don't not get to the express platform heading North at Bedford

 

[tbtc]

The call at Bedford to switch over if it can't be done on the move, although it would probably actually add around 10 - 12 minutes.

Anyway, the wires don't not get to the express platform heading North at Bedford

Twelve minutes for one stop?

I appreciate it takes time to slow down/speed up etc, but if everything stopped there, and they scrapped Luton/ Luton Airport stops then you'd get five trains running at uniform speed from St P to Bedford which would make things a lot lot simpler

 

[MCR247]

12 minutes, to slow down, put pan down and start engines while boarding etc waiting for engines to warm up properly, get back to linespeed etc

But coming into Bedford heading south might get awkward:

Platform 1A - LM to Bletchley lets ignore
Platform 1 - Wired used by FCC
Platform 2 - Wired used by FCC and very occasionally EMT if a FCC is in 3
Platform 3 - Wired used jointly by FCC and EMT southbound
Platform 4 - Not wired used by EMT northbound

So if EMT had to stop all trains at Bedford, that would then mean that FCC would have a much more limited use of platform space. So I could see that FCC would have to have shorter turnaround times, terminate at Luton, send units ECS to Cauldwell while inbetween services none of which are ideal. They could share platforms for 4 car services, but some are 8

 

[tbtc]

12 minutes, to slow down, put pan down and start engines while boarding etc waiting for engines to warm up properly, get back to linespeed etc

But coming into Bedford heading south might get awkward:

Platform 1A - LM to Bletchley lets ignore
Platform 1 - Wired used by FCC
Platform 2 - Wired used by FCC and very occasionally EMT if a FCC is in 3
Platform 3 - Wired used jointly by FCC and EMT southbound
Platform 4 - Not wired used by EMT northbound

So if EMT had to stop all trains at Bedford, that would then mean that FCC would have a much more limited use of platform space. So I could see that FCC would have to have shorter turnaround times, terminate at Luton, send units ECS to Cauldwell while inbetween services none of which are ideal. They could share platforms for 4 car services, but some are 8

Yeah, but FCC are only using Bedford to terminate/start a fifteen minute service, so I can't imagine they'd need three platforms for that

 

[Kingfisher200262]

12 minutes, to slow down, put pan down and start engines while boarding etc waiting for engines to warm up properly, get back to linespeed etc.

I would have thought this delay will be mitigated by the designers building in two features: -

1. Electric heaters on the engine cooling water circuits, to pre-heat the engines;
2. Engine start / stop controls that are linked to GPS and the train plan, which will anticipate demand and start the engines automatically to ensure sufficient power is available.

Another product that is currently being developed, based on the principle of mixed power (electric and diesel), incorporates both of these features.

 

[paul1609]

To be honest I can only imagine that this project would be suitable for short extensions diversions away from the overhead at relatively slow speed.
I dont think there would be the room underneath the extra coaches for diesel engines and their associated exhaust systems assuming that you want the extra coaches to carry passengers.
Assuming you converted a 221 to 7 coaches with two motored pantographs according to my back of the fag packet calculations youd have a power to weight ratio of around 8.70.
On diesel power with the 5 existing engines running youd have performance slightly worse than a class 170 dmu. 4 engines on a 6 coach 220 conversion would seem to be a bit of a non starter.
I reckon a balancing speed in the high 80s/low 90s with quite slow acceleration.
Might be okay to divert off the WCML to serve Manchester via Bolton or Blackpool.
Probably okay for Hull and Lincoln off the ECML.
Not enough power for most XC routes or the MML.
An interesting engineering project though.

 

[asylumxl]

Considering Voyagers and Meridians can keep time with engines isolated, I do imagine that they should have no problem hauling the extra coaches around.

 

[MCR247]

Yeah, but FCC are only using Bedford to terminate/start a fifteen minute service, so I can't imagine they'd need three platforms for that

I think they do, I've been to Bedford quite often and I have seen them using all three platforms at one time on a Saturday
--- old post above --- --- new post below ---
I'm just looking at the 377/5 diagrams and presuming 319s are the same they have a 15-20 minute turnaround at Bedford. So they definitely need two platforms at a time, but I don't think that leaves all that much flexibility. Also wouldn't you have the problem of all of the trains getting really busy, as why would you use FCC when you have almost a 5tph to St Pancras on EMT?

 

[tbtc]

I think they do, I've been to Bedford quite often and I have seen them using all three platforms at one time on a Saturday
--- old post above --- --- new post below ---
I'm just looking at the 377/5 diagrams and presuming 319s are the same they have a 15-20 minute turnaround at Bedford. So they definitely need two platforms at a time, but I don't think that leaves all that much flexibility. Also wouldn't you have the problem of all of the trains getting really busy, as why would you use FCC when you have almost a 5tph to St Pancras on EMT?

I suppose FCC could always step back. Works on the Tube...

I'd make Bedford "set down" / "pick up". We don't have a lot of spare capacity on the MML, and we shouldn't waste it on short distance trips for people who have a frequent EMU alternative (same as East Cost at Stevenage)

 

[YorkshireBear]

or we could just electrify it to leicster and corby cant cost that much, all EMT trains stop at leicster or corby so therefore youre fine to change over st station.

 

[atomicdanny]

I just had this random though, is it just AC Electric (i.e. a pantograph) being added or would it also include a 3rd rail shoe, since a few voyagers do go on it between Basingstoke and Bournemouth!, not much but it would also add up though over time?

 

[YorkshireBear]

not really worth it i dont think cost benifit wouldnt be good for such a short distance,

I'm still sceptical about performance issues after upgrade :/

 

[MCR247]

or we could just electrify it to leicster and corby cant cost that much, all EMT trains stop at leicster or corby so therefore youre fine to change over st station.

Well then why not just electrify the rest?

This is just meant to be until they electrify all of it

 

[YorkshireBear]

Well then why not just electrify the rest?

This is just meant to be until they electrify all of it

i just meant as a stepping stone.... cos stoppping every train at bedford seems a bit pointles...

 

[MCR247]

But why electrify to Leicester? By the time the gov have decided to do it, why not do the rest otherwise it will never get done