TfW class 398 Stadler Citylink tram trains

[VR494]

Can you expand on what you mean by this? Looking at yesterday (Thursday) as an example, the 756s ran a good service all day on this route, with the exception of one service which was terminated short at Heath High Level to recover service after a delay. This route is already at the enhanced timetable of 4 trains per hour, which doesn’t require 30 second dwells at all stations. And in any case 30 second dwells are frequently being achieved at stations where it is timetabled.

It’s not the final timetable design, and no it’s not working well behind the scenes and requires input from control daily to prevent cancellations. If a Coryton is only +3 late it throws the whole paths out with Rhymney line services.

Going forward the time it takes for the doors to release, steps extend and close etc is coming in at 40/50 seconds per stop. The enhanced metro times will only allow 30 seconds or less per stop and they are too slow.

 

[Falcon1200]

So a doubling of frequency from each valley to the centre of Cardiff, and you're questioning whether or not it's a service improvement?

Think we will have to wait until the service actually starts and see what the passenger reaction is! More trains is of course a Good Thing... As long as they go when and where people want to.

 

[AdamWW]

If a Coryton is only +3 late it throws the whole paths out with Rhymney line services.

So far as I can see a huge amount of the disruption is caused by the fact that Heath Junction is almost always set for a train coming down from Caerphilly well before it reaches the junction.
So a train from Coryton arriving at Low Level 3 minutes late misses its path at the junction and just sits there waiting for the train it should have gone in front of to pass, even though there would have been plenty of time for the train from Coryton to pass the junction without actually delaying the train from Caerphilly.
I'm sure there is a very good reason it's done like this, and I appreciate the logic behind setting the path at a junction so drivers don't get a yellow aspect on approach. But as all trains from Caerphilly are timetabled to call at Heath High Level, it's not obvious to me why it matters in this case - whether they get yellow or green at the signal before the junction, they're going to stop at the next signal anyway.
This is then compounded by the frequent decision to turn delayed trains at Heath and have them sit there even for 15 minutes or so rather than running further up the line, or indeed going the whole way but skipping stations.

Going forward the time it takes for the doors to release, steps extend and close etc is coming in at 40/50 seconds per stop.

That agrees with my experience - and it doesn't seem to be compensated for by improved acceleration between stations.

But much of this is caused by the way the doors are currently worked, not the trains themselves. If the doors were worked from a cab (either by the driver or a guard in the rear cab) then dwells would still be longer than a non low floor train as time is still needed for ramps to deploy and retract, but it would only be 2 cycles per station, not 4.

So I'd have thought a 398 would be just as bad if worked in the same way, unless they are set up so that all ramps extend when the ramp goes out for the local door and maybe the local door can be shut without having to wait for the alarm to sound. And maybe their ramps are quicker?

Currently though the Coryton Line seems to just about work with Ty Glas closed - but perhaps trains are being driven to arrive at Heath when they need to, and when Ty Glas reopens they will be driven a bit harder to make up the extra time they need.

 

[slowroad]

Think we will have to wait until the service actually starts and see what the passenger reaction is! More trains is of course a Good Thing... As long as they go when and where people want to.

For me this the really interesting question. Is there sufficient latent demand across all/most of the system to support a metro-style frequency (at least at an affordable cost)?

 

[AdamWW]

For me this the really interesting question. Is there sufficient latent demand across all/most of the system to support a metro-style frequency (at least at an affordable cost)?

Time will tell.

Anecdotally, the ridership on the Coryton Line seems to have gone up somewhat just with the introduction of new trains and no improvement in frequency.

 

[Phillipimo]

Running 12 trains an hour to the heads of the valleys is going to be an issue under the current signal set up. It was no doubt thought of in an office to make a statement.

Some of the sections are still 2 aspect and the rest is 3. Some of these are very long in length too. It’s been said it’s not possible, but they’ll give it a go, it will have issues. They struggle now with the current situation to manage delays. There’s also going to be one signaller controlling all that from Taffs well!

Just to pick up on this point. 12 trains per hour is one every 5 minutes on average. The current Train Planning Rules show a 3 or 3.5 minute headway depending on direction between Pontypridd and Radyr, so the signalling system can definitely handle it. In the current timetable there are trains that follow 5 minutes behind another so I'm not sure where you see the issue.

Certainly the single track sections are a weak point which will have to be managed carefully.

 

[WelshBluebird]

For me this the really interesting question. Is there sufficient latent demand across all/most of the system to support a metro-style frequency (at least at an affordable cost)?

To me this is a much more complex question that is more about what we as a society want to encourage and build for.

Even as someone who is heavily pro public transport and thinks areas like the south Wales area need more frequent services, I do think that for decent amount of time 4 trains per hour at the heads of the valleys and 12 north of Pontypridd is technically overkill in terms of pure capacity.

However, to me its about giving people the option. Having such frequent services is what is needed to give people a genuine alternative to the car. So even if the services are lightly used at some times, its still worth it to provide that service. Its the frequency that makes it such a compelling prospect.

And of course for commuting and during large events the services absolutely will be well used.

 

[Caaardiff]

For many people the difference between a 15-20 minute wait and a 30-60 minute wait can influence the decision whether a bus, taxi or if they have a car, driving themselves is more appealing

 

[VR494]

For many people the difference between a 15-20 minute wait and a 30-60 minute wait can influence the decision whether a bus, taxi or if they have a car, driving themselves is more appealing

With an increase in trains in the sections the travel time is going to increase too. There will be a lot of red signals the whole way.

The biggest problem they have overlooked is the leisure travel on weekends. The flirts are usually packed coming down the valleys from 12pm onwards. Now if you have a family of young children, as you know one of them is going to want the toilet at some point. You now have to think, use the car and just go to the nearest McDonald and spend your money there. Or catch a 398, have to get off in the rain and use a toilet that will no doubt be full of things you’d not want to encounter and then wait for another service in the rain, that could end up being cancelled, which has now made your journey longer than before.

The majority of customers travel from the top of the valley to Cardiff, they don’t get off in between stops. The other customer base is heavily focused around student travel between Cathays and Trefforest. And in my opinion not all trains need to call at the estate, it’s ridiculous.

 

[slowroad]

To me this is a much more complex question that is more about what we as a society want to encourage and build for.

Even as someone who is heavily pro public transport and thinks areas like the south Wales area need more frequent services, I do think that for decent amount of time 4 trains per hour at the heads of the valleys and 12 north of Pontypridd is technically overkill in terms of pure capacity.

However, to me its about giving people the option. Having such frequent services is what is needed to give people a genuine alternative to the car. So even if the services are lightly used at some times, its still worth it to provide that service. Its the frequency that makes it such a compelling prospect.

And of course for commuting and during large events the services absolutely will be well used.

All fair points. But is still a matter of balance…..you can’t have very frequent trains everywhere, and irrespective of cost. As someone else said, I guess it’s a matter of waiting and seeing.

 

[Chris125]

When the original idea was brought about the range capacity of the 398’s was sadly overlooked. They are off the shelf to be run on pure OLE, just like you see in Manchester. They wanted battery power for only small sections off earthed wire under bridges.

I've never seen that suggested and it makes no sense; if nothing else they were designed for street running without wires

 

[Caaardiff]

With an increase in trains in the sections the travel time is going to increase too. There will be a lot of red signals the whole way.

The biggest problem they have overlooked is the leisure travel on weekends. The flirts are usually packed coming down the valleys from 12pm onwards. Now if you have a family of young children, as you know one of them is going to want the toilet at some point. You now have to think, use the car and just go to the nearest McDonald and spend your money there. Or catch a 398, have to get off in the rain and use a toilet that will no doubt be full of things you’d not want to encounter and then wait for another service in the rain, that could end up being cancelled, which has now made your journey longer than before.

The majority of customers travel from the top of the valley to Cardiff, they don’t get off in between stops. The other customer base is heavily focused around student travel between Cathays and Trefforest. And in my opinion not all trains need to call at the estate, it’s ridiculous.

There's countless other scenarios similar to that. One of the biggest ones will be people on nights out.

It's very short sighted of TFW in these plans, but they are in too deep now. The units are delivered, the depot is built.
The only parts of that network seeing trams should have been Pontypridd and Caerphilly to Cardiff. All well within the timescales of other tram networks with no toilet on board. Everything else should have been Flirts.


But we can go around in circles discussing the same things, it's what happens from here that will make a difference. If Cardiff Crossrail grows as planned, then the scope should be to use the current 398s on that network and buy more Flirts. The issue then becomes is there sufficient space in Canton and Barry, and the outstation to stable them.

 

[david1212]

.... and it doesn't seem to be compensated for by improved acceleration between stations.

Going forward the time it takes for the doors to release, steps extend and close etc is coming in at 40/50 seconds per stop. The enhanced metro times will only allow 30 seconds or less per stop and they are too slow.

.....
But much of this is caused by the way the doors are currently worked, not the trains themselves. If the doors were worked from a cab (either by the driver or a guard in the rear cab) then dwells would still be longer than a non low floor train as time is still needed for ramps to deploy and retract, but it would only be 2 cycles per station, not 4.

So I'd have thought a 398 would be just as bad if worked in the same way, unless they are set up so that all ramps extend when the ramp goes out for the local door and maybe the local door can be shut without having to wait for the alarm to sound. And maybe their ramps are quicker?
.....

Much of this seems to be a repeat of why a certain line that had a lot of infrastructure work and rebuilt trains can not actually provide the service intervals / frequency that was promised. To provide a reliable timetable the options have turned out to be either commence/terminate services short or run at a lower frequency.

Time will tell if the same choices have to be made for services operated by the class 398 sets.

 

[VR494]

Much of this seems to be a repeat of why a certain line that had a lot of infrastructure work and rebuilt trains can not actually provide the service intervals / frequency that was promised. To provide a reliable timetable the options have turned out to be either commence/terminate services short or run at a lower frequency.

Time will tell if the same choices have to be made for services operated by the class 398 sets.

The doors on the 398's are a lot quicker to open and close. The method of work proposed for them previously outlined would also be the same for the 756's, and it's no good for the metro times.

The 398's are just a big tick box for now, if they can get atleast one out for May they don't have to return any money to the EU.

The May TT this year won't see change on the CVL and there is no 4 trains an hour in it.

Taffs Well looks like it's become the new parliament chamber, and the South Wales Metro is just one big disfucntional jigsaw, that can't be joined up until they pay for the missing bits.

 

[WelshBluebird]

There is no 4 trains an hour in it.

Nobody has suggested it would be there from May?
Just that they will start introducing the units.
Then is a process of getting the existing services to be run with them before I assume finally then making the timetabling changes.
How long that process is who knows, but they certainly haven't said it would be done by May as thats just the start.

 

[VR494]

Nobody has suggested it would be there from May?
Just that they will start introducing the units.
Then is a process of getting the existing services to be run with them before I assume finally then making the timetabling changes.
How long that process is who knows, but they certainly haven't said it would be done by May as thats just the start.

It won't be this year, until Cardiff West is done to allow x4 up the city line, and they complete the works down the bay. Only the wires will be live by May, which will give the 398's a place to go to get a top up. It's then going to be until atleast spring next year before they start on the remodel down there and Queen Street.

 

[John R]

It won't be this year, until Cardiff West is done to allow x4 up the city line, and they complete the works down the bay. Only the wires will be live by May, which will give the 398's a place to go to get a top up. It's then going to be until atleast spring next year before they start on the remodel down there and Queen Street.

Surely the 4tph is not dependent on Cardiff West being done, as the timetable plan for that has only ever been predicated on 2tph on the city line?

 

[VR494]

Surely the 4tph is not dependent on Cardiff West being done, as the timetable plan for that has only ever been predicated on 2tph on the city line?

Yes, unfortunately Cardiff West junction needs modifications for x4 an hour on the city line, and this is something that was included in the recent announcement of funds from the UK government. The city line will form a key part of the timetable under Mega loop!

Cardiff Bay is due to go live soon, as early as March, so the 398’s will have a power top up down there, before coming back up to Pontypridd.

Once they pan down north of Cathays, they will have around 6.5 miles of battery and a little in reserve for emergency auxiliary power, this will need to get them into Cardiff Central, terminate and come back again. Or continue back around the city line.

With Rhymney line services crossing over as well, they will encounter delays which will also put further strain on the range. If the pantograph then won’t go back up for whatever reason, whether this be a beacon issue, as they have been experiencing, it’s ‘Houston’ we have a problem, or as some have called it (Fred Flinstone mode).

For comparison the class 756 when they pan down, have 90 miles of range on 4 batteries.

 

[Peter Sarf]

Yes, unfortunately Cardiff West junction needs modifications for x4 an hour on the city line, and this is something that was included in the recent announcement of funds from the UK government. The city line will form a key part of the timetable under Mega loop!

Cardiff Bay is due to go live soon, as early as March, so the 398’s will have a power top up down there, before coming back up to Pontypridd.

Once they pan down north of Cathays, they will have around 6.5 miles of battery and a little in reserve for emergency auxiliary power, this will need to get them into Cardiff Central, terminate and come back again. Or continue back around the city line.

With Rhymney line services crossing over as well, they will encounter delays which will also put further strain on the range. If the pantograph then won’t go back up for whatever reason, whether this be a beacon issue, as they have been experiencing, it’s ‘Houston’ we have a problem, or as some have called it (Fred Flinstone mode).

For comparison the class 756 when they pan down, have 90 miles of range on 4 batteries.

Four batteries on the 756s ?.

If you are talking about the power car that has room for four battery pods but one pod/location has a diesel engine in it. That means less battery but of course after the batteries are, potentially, depleted a diesel engine and fuel is even more resilient !.

No idea how the batteries on a 398 compare to even one pod of batteries on a 756 - probably rather small.

 

[VR494]

Four batteries on the 756s ?.

If you are talking about the power car that has room for four battery pods but one pod/location has a diesel engine in it. That means less battery but of course after the batteries are, potentially, depleted a diesel engine and fuel is even more resilient !.

No idea how the batteries on a 398 compare to even one pod of batteries on a 756 - probably rather small.

Yes, that's correct. There are 4 batteries on a 756 and a diesel generator located in the main powerpack. This can work either in combined mode or on it's own. However in just diesel this mode is hardly able to move the unit.

There is one battery on a 398 and they came with a small supply of spares, which some have been fitted with already due to the amount of time they have been sat around.

 

[Peter Sarf]

Yes, that's correct. There are 4 batteries on a 756 and a diesel generator located in the main powerpack. This can work either in combined mode or on it's own. However in just diesel this mode is hardly able to move the unit.

There is one battery on a 398 and they came with a small supply of spares, which some have been fitted with already due to the amount of time they have been sat around.

I think there can only be a maximum of three sets of batteries on the 756s because the fourth location is occupied with the diesel engine ?.

How big (power) these sets of batteries are compared to a 398 I do not know. I suspect the battery capacity on a 756 is a lot more than on a 398 as the 756s are meant to stray further from the electrification than currently while on the TAM lines.

 

[VR494]

I think there can only be a maximum of three sets of batteries on the 756s because the fourth location is occupied with the diesel engine ?.

How big (power) these sets of batteries are compared to a 398 I do not know. I suspect the battery capacity on a 756 is a lot more than on a 398 as the 756s are meant to stray further from the electrification than currently while on the TAM lines.

The 756/1 and 756/0 have x4 ABB lithium titanium oxide ess storage modules, and two BTMS for conditioning. 3-car units have an installed battery capacity of 447 kWh, whilst the 4-cars have a capacity of 559 kWh. They are permitted to run in service with one ess isolated, once they go down to only two, the dynamic braking is lost. This can be topped up with the diesel GU, however the batteries need to be below 20% before it can be started.

The 398's have a totally different setup, and the majority of the electrics are located in the roof of the unit. They are rated at 128kWh and can deliver around 600kW. The acceleration is rapid I will say that, and passengers will notice a difference.

 

[Peter Sarf]

The 756/1 and 756/0 have x4 ABB lithium titanium oxide ess storage modules, and two BTMS for conditioning. 3-car units have an installed battery capacity of 447 kWh, whilst the 4-cars have a capacity of 559 kWh. They are permitted to run in service with one ess isolated, once they go down to only two, the dynamic braking is lost. This can be topped up with the diesel GU, however the batteries need to be below 20% before it can be started.

The 398's have a totally different setup, and the majority of the electrics are located in the roof of the unit. They are rated at 128kWh and can deliver around 600kW. The acceleration is rapid I will say that, and passengers will notice a difference.

Indeed. More tram like vehicles tend to have higher acceleration. On a line with frequent stops acceleration is more use than a top speed that never gets reached.

It seems from your figures that a 398 has 29% of the battery capacity of a 3car 756. So the given the 398s are presumably lighter I would expect the result to be a range of VERY approximately 50% that of a 3car 756. That should be quite a distance.

 

[VR494]

Indeed. More tram like vehicles tend to have higher acceleration. On a line with frequent stops acceleration is more use than a top speed that never gets reached.

It seems from your figures that a 398 has 29% of the battery capacity of a 3car 756. So the given the 398s are presumably lighter I would expect the result to be a range of VERY approximately 50% that of a 3car 756. That should be quite a distance.

It's coming in at around 22 miles on each ESS on a 756, that's on a full charge. You are not far off that this should be around 50% on a 398, the units weigh not much less than a 2 car sprinter though at 73 ton. Stadler techs are saying it's around 6.5 miles of operational use before the rest is needed for essential systems. There are some test runs planned around the loop coming up in the early hours, so we'll see.

 

[allaction]

Let’s hope that the 398’s don’t turn into a waste of public money like the support for the doomed Circuit of Wales project at Ebbw Vale proved to be.

How much funding will need to be returned to the EU if even one is not running by May?

 

[VR494]

Let’s hope that the 398’s don’t turn into a waste of public money like the support for the doomed Circuit of Wales project at Ebbw Vale proved to be.

How much funding will need to be returned to the EU if even one is not running by May?

The plan is to still have a unit out for sometime in May, it's all hands on deck to try and make it happen. Most likely it will be either 398023, 398029 or 398031. How realiable these units prove to be though when in service - only time will tell.

 

[Lurcheroo]

Stadler techs are saying it's around 6.5 miles of operational use

Ok, but Stadler said this (10km) atleast as far back as in 2022 so it’s not a surprise to TFW or anyone involved ?

 

[VR494]

Ok, but Stadler said this (10km) atleast as far back as in 2022 so it’s not a surprise to TFW or anyone involved ?

They did, and as these two interviews point out, operational challenges meant that full OLE for even the discountious bits was not possible. What was ordered now will have to adapt going forward to where they are at.

 

[meld3]

What everyone needs to remember, is that battery development is running exponentially as present, and just as 2022 was a very long time ago battery wise, 3-5 years from now, fully working solid state battery weighing half as much for the same capacity will likely be available. Given the lifetime of these units will be 30-40 years, I'm sure we will see several large improvements over time as the technology matures.
A few years ago I had zero interest in batteries, but a year in an EV has got my trusty anorak thirst for chemistries, charging specs, and anything with the letters k, W and h.

 

[VR494]

What everyone needs to remember, is that battery development is running exponentially as present, and just as 2022 was a very long time ago battery wise, 3-5 years from now, fully working solid state battery weighing half as much for the same capacity will likely be available. Given the lifetime of these units will be 30-40 years, I'm sure we will see several large improvements over time as the technology matures.
A few years ago I had zero interest in batteries, but a year in an EV has got my trusty anorak thirst for chemistries, charging specs, and anything with the letters k, W and h.

The trouble is Stadler are just completing an order that was placed many years ago, and only 3 more units are left to be produced I believe. Upgraded batteries would be ideal, but I don't think the product in general offers that at the moment.

What you may see though is these units may end up just being confined to the Cardiff Bay branch from the three peaks. The range is too much of a risk to have them fail in Cardiff Central and end up rocking up costs in delays. Seeing as some stations are also located in PES sections on the TAM, any delay for toilet stops is also out of the question. They need to keep going to stay under the wires as much as possible.