• Our new ticketing site is now live! Using either this or the original site (both powered by TrainSplit) helps support the running of the forum with every ticket purchase! Find out more and ask any questions/give us feedback in this thread!

Transport for Wales Class 231 / 756 FLIRTs

MikePJ

Member
Joined
10 Dec 2015
Messages
706
So maybe not yet enough wiring up the Rhymney valley for the Caerphilly Southwards part to be usable by 756s yet ?.
I think the Rhymney line is the one where 756s are supposed to actually be iirc ?.
Hi Peter - yes, the wires between Caerphilly and Heath and betweeen Coryton and Heath are not yet live. They were supposed to go live in October 24, then in February this year (and TfW actually put out press releases in advance saying it had happened) and then the actual energisation didn't happen for some reason. Until they're energised the 3-car 756s can't start service on these routes. 756007 has been out on the Aberdare line most days doing driver training. There's a big system shutdown over the weekend of April 5th/6th so that's the next likely date for energisation.
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

Peter Sarf

Established Member
Joined
12 Oct 2010
Messages
7,677
Location
Croydon
Thankyou both for your replies.
Can't help on the infrastructure element I'm afraid.

Diagram wise the Rhymneys are all showing as 150/153/231 operated from the timetable change so that would tally that only diesels can get there but I'm not in a position to confirm that.
+
Hi Peter - yes, the wires between Caerphilly and Heath and betweeen Coryton and Heath are not yet live. They were supposed to go live in October 24, then in February this year (and TfW actually put out press releases in advance saying it had happened) and then the actual energisation didn't happen for some reason. Until they're energised the 3-car 756s can't start service on these routes. 756007 has been out on the Aberdare line most days doing driver training. There's a big system shutdown over the weekend of April 5th/6th so that's the next likely date for energisation.
So switching on of a large area (Heath to Coryton & Caerphilly) of electrification could well be imminent (Early April 2025).
Must be tantalisingly close to the pressure being taken off the 150s and all the 756s being usable one way or another.

Then it will just be any loose ends (only ?) on the TAM lines and then see how the 398s roll out ?.
Then I suppose 756s can move from TAM to Rhymney lines with 231s moving on to what they were ordered for (Maesteg - Cheltenham iirc).

At last will be running out of things to go wrong or get implemented late.
 

MikePJ

Member
Joined
10 Dec 2015
Messages
706
Thankyou both for your replies.

+

So switching on of a large area (Heath to Coryton & Caerphilly) of electrification could well be imminent (Early April 2025).
Must be tantalisingly close to the pressure being taken off the 150s and all the 756s being usable one way or another.

Then it will just be any loose ends (only ?) on the TAM lines and then see how the 398s roll out ?.
Then I suppose 756s can move from TAM to Rhymney lines with 231s moving on to what they were ordered for (Maesteg - Cheltenham iirc).

At last will be running out of things to go wrong or get implemented late.
Once the wires are live there will need to be test runs and driver familiarisation, which is why TfW have put the start date for 756s on Coryton/Caerphilly/Penarth back to "spring/summer" (May or June at the earliest, I think). There's a lot of big shutdowns on the northern Rhymney line from April onwards to finish off the overhead wiring and trackwork. This is scheduled to be complete in December but I would expect it to slip into 2026.

398s are now being talked about for entry into service in late 2025 and early 2026 - there's mileage accumulation and driver training still to do.
I would not get your hopes up about the 231s moving any time soon!

One other big missing piece is that there's supposed to be a big track and signalling upgrade at Queen Street which should be happening around now but doesn't appear to have been announced. This is needed to support the enhanced 6tph service to/from Cardiff Bay, with all Bay trains running to Treherbert, Aberdare or Merthyr. Given the general delays, I wouldn't be surprised if we see the current timetable operated mostly/entirely with electric trains before the Queen St upgrade happens.
 

Cardiff123

Established Member
Joined
10 Mar 2013
Messages
1,421
And 150s held together with sticky tape and plasters will be running on the VoG until mainline drivers are trained on 756s........sometime in 2027 or 2028........
 

craigybagel

Established Member
Joined
25 Oct 2012
Messages
5,531
And 150s held together with sticky tape and plasters will be running on the VoG until mainline drivers are trained on 756s........sometime in 2027 or 2028........
The same mainline drivers who work the majority of VOG services are the ones who work most of the Maesteg & Ebbw Vale services (ie the least senior links at Cardiff Mainline). They'll need to learn 231s for the latter services, and it's only a 2 day conversion onto 756s IIRC. It wouldn't surprise me if they come up with a package to combine the training together.
 

Cardiff123

Established Member
Joined
10 Mar 2013
Messages
1,421
The same mainline drivers who work the majority of VOG services are the ones who work most of the Maesteg & Ebbw Vale services (ie the least senior links at Cardiff Mainline). They'll need to learn 231s for the latter services, and it's only a 2 day conversion onto 756s IIRC. It wouldn't surprise me if they come up with a package to combine the training together.
That's good to know, most of my posts are dripping in sarcasm lately so don't take them literally, but in all seriousness, I fully understand these things take time and everywhere will get the benefits eventually.
 

AdamWW

Established Member
Joined
6 Nov 2012
Messages
4,574
Like I said, marketing spiel does not match on the ground reality. Maybe TfW press should keep quiet and rein in their advertising spend until said trains are actually reliably in service every day.

Progress is not linear, and when has marketing of any product or service ever matched reality?

Perhaps but it's somewhat frustrating when things are pretty dire on the ground that instead of any admission that there is a problem there's just a relentless stream of positive PR.

E.g. shutting down a line for 2 weeks at a few days notice with no explanation or apology, just a press release about how wonderful it is that they are doing electrification work.

The delay to the introduction to these units is because of the electrification - it should have gone live in November, and then was kicked back to February, and then we got very close to it and for some reason it was delayed again. It's likely to be to do with safety assessments for the interface between the wires and the surrounding buildings and structures, but we haven't had any formal confirmation of this yet. The Coryton service runs Coryton-Penarth-Caerphilly and return which is why Lisvane, Llanishen and Heath are mentioned in the press release.

Still no extended parapets on many of the bridges over the wires which are to go live. Maybe they're not needed somehow (though I can't think of anywhere else in the UK I've seen such low parapets over live wires).

It is so obvious that many of the armchairs critics in these boards have no idea how major projects like this work. One small bit of electrification infrastructure not working can set the project back weeks. Remember you are trying to upgrade a working railway. There are only so many opportunities you can have to carry out engineering works and these need to be planned weeks in advance. It may look amateurish to the lay person but it will happen as fast as it can. The only way to speed it up is close it all down and just work on it 24/7.

Well of course there have been times when they have just shut everything down for an extended period. And, unlike the rest of the network, TfW don't appear to need to plan weeks in advance - they can just shut lines down at a few days notice if convenient for them.

TfW doesn't look hugely competent to this lay person. I appreciate that often there are good reasons that aren't apparent but when I see what looks like poor decision making over and over and over again it starts to feel as if maybe it is just poor decision making.

I would argue that just as an outsider might be wrong in thinking that things could be done better, it's just as much of a mistake to assert from the outside that everything must be being done in the best possible way and that there is no scope for improvement.

Coryton is difficult to replace with a bus as there is no convenient parallel road.

And of course they don't bother. Just use your ticket on Cardiff Bus (if they've bothered to actually arrange it) and if you wanted to travel between two intermediate stops then it's a rail replacement walk for you.

One other big missing piece is that there's supposed to be a big track and signalling upgrade at Queen Street which should be happening around now but doesn't appear to have been announced.

Which might just mean they don't know the exact dates and a major closure will suddenly (and quietly) appear on the service disruption pages at short notice.

Unfortunately this is just not good enough, TfW keep kicking the can down the road on new train introduction and finding excuses for their poor performance. This press release has only been put out because they've been shamed into it by 3 of the Coryton line stations being in the top ten of most cancelled services in the UK.

I'm intrigued by the suggestion that the 756s will improve punctuality by having more carriages and doors. Clearly when they're busy people will get on and off faster than a single 153. I'm not so sure they'll make much of a difference compared to 150s. And the minimum dwell time is considerably longer because of the time to extend and retract steps - which has to be done separately for the local door as well as the other doors (and unlike a 15x you even have to wait for the alarm to sound before the local door will shut).
 
Last edited:

Bob Price

Member
Joined
8 Aug 2019
Messages
1,157
Suddenly appear? This was at Heath High Level today.
 

Attachments

  • PXL_20250315_155103207.jpg
    PXL_20250315_155103207.jpg
    2.1 MB · Views: 157

Bob Price

Member
Joined
8 Aug 2019
Messages
1,157
Point is closures are planned and advertised. If they did do short notice closures in the past then maybe they have learned from it.
 

sd0733

Established Member
Joined
7 Nov 2012
Messages
4,608
With the International yesterday did the number of 756s reach their highest in service number?
There were 8 in service yesterday (756103/105/107/109/111/113/114/115). Higher than normal but not too sure if it's the highest day so far
 

AdamWW

Established Member
Joined
6 Nov 2012
Messages
4,574
If anyone wants to watch the 756s raising and lowering their pantographs on the fly, there's a good view looking across the Taff just north of Radyr station. Fortunately it happens just before/after the line moves away from the river and vanishes into trees.
 

Cardiff123

Established Member
Joined
10 Mar 2013
Messages
1,421
Still no extended parapets on many of the bridges over the wires which are to go live. Maybe they're not needed somehow (though I can't think of anywhere else in the UK I've seen such low parapets over live wires).
The wires won't be live under low bridges, those will be neutral permanently earthed sections, this has saved TfW the considerable cost and disruption of raising the many low bridges on the network.
 

AdamWW

Established Member
Joined
6 Nov 2012
Messages
4,574
The wires won't be live under low bridges, those will be neutral permanently earthed sections, this has saved TfW the considerable cost and disruption of raising the many low bridges on the network.

Actually no.

These bridges will definitely have live wires under them. Close to the undersides and I believe it's made possible by using surge arresters so the clearance can be based on the nominal line voltage not the possible higher voltage under a lightning strike. Maybe also insulating paint.

Clearly a change of plan because I've seen drawings showing multiple earthed sections that didn't end up happening. And there was a fair amount of trunking installed with nothing in that was presumably to carry the power through these sections.

In any case TfW seem to install raised parapets over permanently earthed sections anyway - possibly not keen to make it too obvious which bits could be safely liberated?

I'm not sure we're in quite the right thread for this though.
 
Last edited:

AdamWW

Established Member
Joined
6 Nov 2012
Messages
4,574
Interesting! It’s definitely the 3-car that’s been out most often for training trips.

Good to see one going because they would be the obvious ones to use for Caerphilly-Penarth-Coryton services given the platform lengths on the Coryton line.

(Though I don't think they'll fit at Ty Glas)

756 007 in passenger service today according to RTT. I think it is the first 3 car.

I've certainly not noticed anything showing up as 3 cars on realtimetrains.
 

MikePJ

Member
Joined
10 Dec 2015
Messages
706
Good to see one going because they would be the obvious ones to use for Caerphilly-Penarth-Coryton services given the platform lengths on the Coryton line.

Yes, my understanding was that this is what they were intended for.

(Though I don't think they'll fit at Ty Glas)



I've certainly not noticed anything showing up as 3 cars on realtimetrains.
It’s booked to come on duty later today https://www.realtimetrains.co.uk/service/gb-nr:W18372/2025-03-16/detailed
 

positron

Member
Joined
4 Jul 2023
Messages
263
Location
Cardiff
One thing to keep in mind is even once the 756s are on the Caerphilly - Penarth - Coryton services they still have a lot of infrastructure work to do up the Rhymney valley to get them running all the way up. So the 150s / 231s aren't off the hook just yet.
 

AdamWW

Established Member
Joined
6 Nov 2012
Messages
4,574
One thing to keep in mind is even once the 756s are on the Caerphilly - Penarth - Coryton services they still have a lot of infrastructure work to do up the Rhymney valley to get them running all the way up. So the 150s / 231s aren't off the hook just yet.

They also need the 398s in service, of course, so that the 756s can move over.
 

MikePJ

Member
Joined
10 Dec 2015
Messages
706
They also need the 398s in service, of course, so that the 756s can move over.
That's all very true, though of course enough new stock has been purchased to run a more intensive service than is currently run, so it might be possible to get rid of the older diesel units with only a few 398s in service.

A rough calculation: TfW had 36 class 150s and 26 class 153s back in 2021. There are 11x 231s, 36x 398s, 7x 3-car 756s and 17 x 4-car 756s, so a total of 71 new units replacing 62 older ones, and that's without allowing for the 231s and 756s being longer and the fact that some of the 153s are being kept for Heart of Wales Line use.

However, we know ultimately that the plan is for the 398s and 756s to operate the Core Valley Lines services, so that means that 60 units are needed for the final metro 4tph-to-each-valley service. I don't know how many units are needed for the current timetable but I'd guess about 45 as the current service is a bit over half the final frequency. Using all the 231s and 756s gives you 35 units, so another 10 398s might need to be running to be rid of the 150s and 153s?
 

Cardiff123

Established Member
Joined
10 Mar 2013
Messages
1,421
That's all very true, though of course enough new stock has been purchased to run a more intensive service than is currently run, so it might be possible to get rid of the older diesel units with only a few 398s in service.

A rough calculation: TfW had 36 class 150s and 26 class 153s back in 2021. There are 11x 231s, 36x 398s, 7x 3-car 756s and 17 x 4-car 756s, so a total of 71 new units replacing 62 older ones, and that's without allowing for the 231s and 756s being longer and the fact that some of the 153s are being kept for Heart of Wales Line use.

However, we know ultimately that the plan is for the 398s and 756s to operate the Core Valley Lines services, so that means that 60 units are needed for the final metro 4tph-to-each-valley service. I don't know how many units are needed for the current timetable but I'd guess about 45 as the current service is a bit over half the final frequency. Using all the 231s and 756s gives you 35 units, so another 10 398s might need to be running to be rid of the 150s and 153s?
Are all 11 of the 231s in service on the Rhymney/Bargoed to Barry Island diagrams most days?
Looking at RTT, there always seems to be at least 1 Barry Island diagram that is still a 150 and of course Rhymney to Bridgend will still be 150s for the foreseeable future.
 

Rhydgaled

Established Member
Joined
25 Nov 2010
Messages
4,754
Are all 11 of the 231s in service on the Rhymney/Bargoed to Barry Island diagrams most days?Looking at RTT, there always seems to be at least 1 Barry Island diagram that is still a 150 and of course Rhymney to Bridgend will still be 150s for the foreseeable future.
Don't forget that the 756s are tri-modes and were always expected to run significant distances away from the wires and, I think, Rhymney to Heath is slightly shorter than Cardiff to Bridgend via Barry. Admittedly it would require a timetable reshuffle, but if you had (for example) Rhymney-Treherbert and Aberdare-Barry-Bridgend instead then the 756s would probably be capable of running the entire Core ValleyLines network, if there were enough of them.
 

Peter Sarf

Established Member
Joined
12 Oct 2010
Messages
7,677
Location
Croydon
Don't forget that the 756s are tri-modes and were always expected to run significant distances away from the wires and, I think, Rhymney to Heath is slightly shorter than Cardiff to Bridgend via Barry. Admittedly it would require a timetable reshuffle, but if you had (for example) Rhymney-Treherbert and Aberdare-Barry-Bridgend instead then the 756s would probably be capable of running the entire Core ValleyLines network, if there were enough of them.
One problem would be the amount of power to get up the Rhymney Valley versus what I assume is a flatter route Cardiff to Bridgend via Barry.
Also I do not know how complete the electrification is on The TAM lines - is it enough to give the 756s enough charge for enough range for an out and back trip up to Rhymney ?.
 

Top