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Transport for Wales Class 231 / 756 Stadler FLIRTs

positron

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He was confident the Class 756s’ batteries will store enough charge for the units to travel from Cardiff Queen Street to Bridgend via Barry and back without recharging. He did not expect their diesel engines to recharge batteries during the round trip in normal operating conditions.
He is referring to Sandro Muster, Stadler’s Project Manager.

This is the origin of the might not need diesel in general use idea that I mentioned. Obviously a 3 year old article and they're potentially biased into being hopeful about their own product.
 
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MikePJ

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I can understand those areas where there are complex layouts or bridges but there did seem to be some simple areas that didn't on the face of it have any major obstacles
There are a surprising number of factors! Through Cathays, for example, there are no wires to avoid electromagnetic interference to some sensitive equipment in one of Cardiff University's buildings. In other cases it may be that it's not worth inserting wires in a short-ish section between bridges. There was a talk some years ago at a trade association (PWI, I think) from one of the designers and they'd done a lot of computer modelling of how the trains use power in order to decide where electrification was justified and where it wasn't.
 

Caaardiff

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Noticed this by the student accommodation in Cathays that the wires finish. How does that work for the units? Do they have to stop/slow down to pan up and down?
 

Logger79

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Noticed this by the student accommodation in Cathays that the wires finish. How does that work for the units? Do they have to stop/slow down to pan up and down?
Nope, its totally seamless. We only check that the pantograph raises/lowers and the VCB opens and closes, all at normal line speed.
 

AdamWW

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Do they have to stop/slow down to pan up and down?

They change over on the fly and they don't seem to have to slow down for it.

I don't know if there is anywhere useful to watch the process there, but there's good visibility of it happening just north of Radyr from the other side of the Taff.

And if you're on a train on a sunny day you can easily see the shadow of the pantograph as it's raised or lowered.
 

chargesmith

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There are a surprising number of factors! Through Cathays, for example, there are no wires to avoid electromagnetic interference to some sensitive equipment in one of Cardiff University's buildings. In other cases it may be that it's not worth inserting wires in a short-ish section between bridges. There was a talk some years ago at a trade association (PWI, I think) from one of the designers and they'd done a lot of computer modelling of how the trains use power in order to decide where electrification was justified and where it wasn't.
I believe it's a brain scanner in CUBRIC?

Probably possible to shield the interference but given the wires would have stopped just outside Queen Street anyway as it's a complex junction it probably wasn't cost effective. An extra mile of battery operation probably isn't a big deal for the units.
 

nigelsporne

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There are a surprising number of factors! Through Cathays, for example, there are no wires to avoid electromagnetic interference to some sensitive equipment in one of Cardiff University's buildings. In other cases it may be that it's not worth inserting wires in a short-ish section between bridges. There was a talk some years ago at a trade association (PWI, I think) from one of the designers and they'd done a lot of computer modelling of how the trains use power in order to decide where electrification was justified and where it wasn't.
Thanks for this. Obviously not that simple and somebody had done their homework.
 

tigermonstera

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TfW have put out a new video showcasing the 756s on the Coryton-Penarth-Caerphilly Route.
We’ll be introducing 5 of these new trains onto the Coryton, Caerphilly and Penarth routes in a phased approach over the coming months.
The new Stadler-built Class 756 fleet feature three modern, spacious carriages and is capable of operating on overhead line equipment (OLE), battery power, or as a diesel/battery hybrid.
I can't recall them calling that mode a diesel/battery hybrid before now — it is more accurate.
 
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MikePJ

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I believe it's a brain scanner in CUBRIC?

Probably possible to shield the interference but given the wires would have stopped just outside Queen Street anyway as it's a complex junction it probably wasn't cost effective. An extra mile of battery operation probably isn't a big deal for the units.
There’s a brain scanner in CUBRIC and also a Transmission Electron Microscope in the TRH building (behind Sbarc) - the latter is imaging nanometre-scale objects so is very sensitive to noise.
 

Cardiff123

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How true is this statement in the TfW / Welsh Government press release?

The new trains, which provide 50% more capacity and improved accessibility, including level boarding, are being introduced after a successful trial on the Coryton line earlier this year. The line is also set to benefit from a Sunday service, for the first time, from December.
50% extra capacity for a 3 car 756, over a 2 car 150, is being a bit generous isn't it? We know that the 756s have shorter carriages than 150s anyway with less seats per carriage.
 

AdamWW

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How true is this statement in the TfW / Welsh Government press release?


50% extra capacity for a 3 car 756, over a 2 car 150, is being a bit generous isn't it? We know that the 756s have shorter carriages than 150s anyway with less seats per carriage.

A curious read.

I wonder what they're referring to as the "sucessful trial"?

I find it a bit odd that they keep describing 5 diagrams going over to 756s as 5 new trains being introduced - it makes it sound as if they intend to cover them with just 5 trains, and indeed suggests that they're just coming into service now rather than already have been running elsewhere.

It's also a bit disappointing to see the new timetable described as a success when despite their "tweaks" the Coryton Line has still suffered from frequent short notice cancellations.
(Recenttraintimes shows one service as having an 18% cancellation rate over the last 10 weeks).
 
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How true is this statement in the TfW / Welsh Government press release?


50% extra capacity for a 3 car 756, over a 2 car 150, is being a bit generous isn't it? We know that the 756s have shorter carriages than 150s anyway with less seats per carriage.
I'm pretty sure they have pretty much the same number of seats when you include tip-ups. A 756 will have a few more normal seats (10 maybe) and so there's not much in it
 

Cardiff123

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What's the standing capacity of a TfW Class 150? They might be referring to that?
I think it's all what's called "Spin". There's no doubt the 756s are superb trains, but expect a lot of "world beating, look how great we are" claims from TfW and Welsh Government, that maybe exaggerate the facts, between now and mid-March next year, when the strict purdah rules come into force during the Senedd election period.
 

chargesmith

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How true is this statement in the TfW / Welsh Government press release?


50% extra capacity for a 3 car 756, over a 2 car 150, is being a bit generous isn't it? We know that the 756s have shorter carriages than 150s anyway with less seats per carriage.
One could argue that 3 cars instead of 2 is a 50% increase in capacity. Most people will see it that way even if the seating or standing capacity doesn't make it so.
 

AdamWW

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One could argue that 3 cars instead of 2 is a 50% increase in capacity. Most people will see it that way even if the seating or standing capacity doesn't make it so.

It seems a complete mis-use of the word capacity to me.

We could count the power module and say capacity has been doubled...

(Yes I know you're only supposed to walk through it and not stand in there).
 
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What's the standing capacity of a TfW Class 150? They might be referring to that?
3-car 756: 118 seats and 24 tip-up (142 total) with 148 standing spaces.

150: 108 seats and 36 tip-up (144) with 49 standing spaces.

The 150 figures are a mix of pre (standing) and post (seats) refurb so may not be 100% accurate but it's the best I could find.
 

tigermonstera

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3-car 756: 118 seats and 24 tip-up (142 total) with 148 standing spaces.

150: 108 seats and 36 tip-up (144) with 49 standing spaces.

The 150 figures are a mix of pre (standing) and post (seats) refurb so may not be 100% accurate but it's the best I could find.
Based on those figures, it would be a 50% increase in total passenger capacity — just not seating capacity.
 

AdamWW

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Probably the comment about the 5mph speed limit. Trains have data recorders which retain the data for several days after the event.

Ah. Thanks.

I deliberately didn't identify the service. It didn't cross my mind though that based on a social media post someone in management might download the records for the whole day and do some detective work.

I would feel a bit guilty if knew I had triggered something like that, though if it's considered such a serious issue perhaps it shouldn't have happened in the first place.
 

Caaardiff

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3-car 756: 118 seats and 24 tip-up (142 total) with 148 standing spaces.

150: 108 seats and 36 tip-up (144) with 49 standing spaces.

The 150 figures are a mix of pre (standing) and post (seats) refurb so may not be 100% accurate but it's the best I could find.
Based on that the capacity of a 150 is 193, 50% of that is 96.5, so 289.5 total.

The capacity of of 756 3 car is 290. So it's entirely accurate in that sense.

Trains are designed to carry standing passengers, so forms part of the total capacity.

The same as a coach vs a service bus. Coaches aren't designed to carry standing passengers, service buses are.
If you delve into the capacity of a tube train, then the seating capacity vs total capacity is very different.

== Doublepost prevention - post automatically merged: ==

Ah. Thanks.

I deliberately didn't identify the service. It didn't cross my mind though that based on a social media post someone in management might download the records for the whole day and do some detective work.

I would feel a bit guilty if knew I had triggered something like that, though if it's considered such a serious issue perhaps it shouldn't have happened in the first place.
While the trains aren't new to Drivers, the trains on that route are. Maybe it was a Drivers first time driving the 756 on that route without being under instruction.
 

Bikeman78

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Based on that the capacity of a 150 is 193, 50% of that is 96.5, so 289.5 total.

The capacity of of 756 3 car is 290. So it's entirely accurate in that sense.

Trains are designed to carry standing passengers, so forms part of the total capacity.

The same as a coach vs a service bus. Coaches aren't designed to carry standing passengers, service buses are.
If you delve into the capacity of a tube train, then the seating capacity vs total capacity is very different.
Standing on those routes is unlikely, especially Penarth and Coryton. Even the Caerphilly legs won't be that full if they continue to run non stop from Queen Street.
 

AdamWW

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Standing on those routes is unlikely, especially Penarth and Coryton. Even the Caerphilly legs won't be that full if they continue to run non stop from Queen Street.

I would very much hope that they don't have to continue to run non stop once the 756s are fully in place.
 

Anonymous10

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3-car 756: 118 seats and 24 tip-up (142 total) with 148 standing spaces.

150: 108 seats and 36 tip-up (144) with 49 standing spaces.

The 150 figures are a mix of pre (standing) and post (seats) refurb so may not be 100% accurate but it's the best I could find.
Ive never noticed 36 tip up seats , where are they? Sure there's less than that.
 

Bikeman78

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I would very much hope that they don't have to continue to run non stop once the 756s are fully in place.
Agreed. The performance has improved a lot since 150s replaced 153s. Unfortunately that happened around the same time as the stops were pulled out on the Caerphilly runs so it's hard to tell what has caused the improvement.
 

56xx

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There was some fun at Pontypridd today that caused chaos on the valley lines. Officially an issue with a train, but overheard a guard saying a pantograph had hit the platform roof - though that sounds pretty dramatic and odd to me! Did take a while to recover mind you so maybe it was!
There is a short video on Facebook of staff up a ladder on Pontypridd Station Platform 2 trying to lower or free the pantograph on a 756 which had failed to lower and had apparently struck the roof canopy. Comments include that failure to auto lower the pantograph is a regular issue.

Many cancellations and late workings this morning.
 

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