Selective Door Opening (SDO) query

[Batman]

The last few time I've traveled in the 4th coach on the 17:42 Birmingham New Street - Rugeley Trent Valley (the coach which doesn't fit into the platforms at stations north of Walsall), I've noticed a queue forming leading up to the rear set of doors on the 3rd coach of passenger waiting to leave the train. At some stations this line stretches through the doors into the 4th coach. This is especially true when this train is extra busy in the school holidays. On more the one occasion now I've noticed the alarm starting to sound for the doors to close when the back end of the queue is still filing through the bike area.

Is it a proven fact that having 1.5 coaches worth of passengers leaving through 1 set of doors lengthens platform dwell times and does the timetable take account of this?

 

[Qwerty133]

Is this a 2x170 service or a 170 +153 service? Have passengers ever been unable to alight the service before the doors are locked?

 

[Batman]

Is this a 2x170 service or a 170 +153 service? Have passengers ever been unable to alight the service before the doors are locked?

It's a 2x170 service. I've seen a few close calls, but usually alighting passengers activate the sensors which keep the doors open for a few more seconds.

 

[455driver]

It does delay the train, if some of the passengers walked through the 3rd coach to use the other set of doors the train wouldnt be delayed as much.

The alternative is to restrict the train length to what can be accommodated on all the platforms so those same passengers would complain about the overcrowding.

The railway is damned if they do and damned if they dont.

 

[Batman]

It does delay the train, if some of the passengers walked through the 3rd coach to use the other set of doors the train wouldnt be delayed as much.

The alternative is to restrict the train length to what can be accommodated on all the platforms so those same passengers would complain about the overcrowding.

The railway is damned if they do and damned if they dont.

The train in question has passengers standing even with 4 coaches, the maximum the line can take because of the 3 car platforms and the lack of corridor connections on 170's. I dread to think what it would be like with 3 coaches. It was only lengthened from 3 to 4 coaches in December 2011 and now it has roughly the same number of standing passengers as when it was just 3 coaches.

The Chase line needs to have platform extensions included within the electrification project.

 

[455driver]

The Chase line needs to have platform extensions included within the electrification project.

Who pays for that then?

 

[Batman]

Who pays for that then?

Central government, since they're funding electrification.

At the moment it looks like all Chase line services will be 3 car 323's after electrification (where they'll come from, I don't know). 350's are needed to avoid overcrowding in the peaks, but they don't have SDO so platform extensions will be needed.
--- old post above --- --- new post below ---
And remember that Cannock, Landywood, Bloxwich North and Bloxwich still have the 'temporary' wooden platforms that were belt in the 1980's and urgently need replacing with more permanent concrete structures.

 

[Muzer]

Central government, since they're funding electrification.

At the moment it looks like all Chase line services will be 3 car 323's after electrification (where they'll come from, I don't know). 350's are needed to avoid overcrowding in the peaks, but they don't have SDO so platform extensions will be needed.
--- old post above --- --- new post below ---
And remember that Cannock, Landywood, Bloxwich North and Bloxwich still have the 'temporary' wooden platforms that were belt in the 1980's and urgently need replacing with more permanent concrete structures.

SWT's "solution" for the lack of SDO on 444s*, at least, is to just open a single door - this can be observed at Shawford whenever a 444 made up of 5-car units stops there. But by the sounds of it this won't be a good solution for THAT line


*Well, they have SDO, but I believe you can only open an entire unit's doors at once, so a 444 with 5-car units won't be usable with a decent number of doors at a 4-car platform.

 

[Lewisham2221]

Central government, since they're funding electrification.

At the moment it looks like all Chase line services will be 3 car 323's after electrification (where they'll come from, I don't know). 350's are needed to avoid overcrowding in the peaks, but they don't have SDO so platform extensions will be needed.
--- old post above --- --- new post below ---
And remember that Cannock, Landywood, Bloxwich North and Bloxwich still have the 'temporary' wooden platforms that were belt in the 1980's and urgently need replacing with more permanent concrete structures.

How would a 350 help the overcrowding, over a 323? Unless I'm getting my maths very wrong (which is very possible at this time of night ), a 323 has more seats than a 350 and isn't a great deal shorter in length. Bear in mind also that the 350's have first class seating and more toilets than a 323 and you'd surely be better off with 323's?

 

[Crossover]

*Well, they have SDO, but I believe you can only open an entire unit's doors at once, so a 444 with 5-car units won't be usable with a decent number of doors at a 4-car platform.

It has been done on here a few times, but for completeness, the Desiros have UDS - Unit Deselect

It does exactly what it says on the tin...deselects all doors on a unit from opening, which means you can have an 8 car 350 service on Rugeley Trent Valley down platform, with 6 coaches on but only 4 open (and TPE similar story when they diverted via Hebden Bridge)

Utterly stupid/useless system if you ask me, but what do I know

 

[the sniper]

Is it a proven fact that having 1.5 coaches worth of passengers leaving through 1 set of doors lengthens platform dwell times and does the timetable take account of this?

There's a fair amount of slack in the timetable on the Chase line so it shouldn't normally be a problem, particularly if the railhead condition is alright. So long as people are ready to get off, there wouldn't be too much of a delay, if any.

 

[swt_passenger]

It has been done on here a few times, but for completeness, the Desiros have UDS - Unit Deselect

It does exactly what it says on the tin...deselects all doors on a unit from opening, which means you can have an 8 car 350 service on Rugeley Trent Valley down platform, with 6 coaches on but only 4 open (and TPE similar story when they diverted via Hebden Bridge)

Utterly stupid/useless system if you ask me, but what do I know

Fortunately the SWT Desiro fleet (and the 458/5s) are now being retrofitted with a 'carriage level' auto SDO to overcome short platform issues where extension is never going to be practical or economical. Dates here: http://www.railforums.co.uk/showpost.php?p=1267461&postcount=10

 

[Batman]

How would a 350 help the overcrowding, over a 323? Unless I'm getting my maths very wrong (which is very possible at this time of night ), a 323 has more seats than a 350 and isn't a great deal shorter in length. Bear in mind also that the 350's have first class seating and more toilets than a 323 and you'd surely be better off with 323's?

You're correct. The current high peak train has 244 seats (2x170/5), a 323 has 284 seats and a 350 only 200 seats.

Although it would mean moving to rolling stock with a high density seating layout, having taken into account the passenger growth and projected rolling stock requirements in the 2011 West Midlands RUS, as well as the morning peak timetable changes that have taken place since then, the Chase line should be ok come 2019 with all 4 diagrams being operated by 323's so long as there is an additional peak time service from Hednesford that calls only at Cannock, Walsall and Tame Bridge and arrives at New Street at about 0820. In other words, bring back the additional peak the was withdrawn in 2011, and have it running semi-fast south of Walsall rather than combining it with a stopping service. This can be done because such a service operated back in Central Trains days.

I'm not sure where the line would go from 2019 though. Maybe platform extensions to 6 car length might be necessary. That would be tricky at some stations such as Bloxwich (location of signaling equipment), Cannock (bridges at both ends of current platforms) and Rugeley Trent Valley. (island platform).

Electrification could turn out to be a victim of it's own success because with DMU's you can be more flexible in deploying rolling stock and can gradually increase train lengths 1 coach at a time.

 

[The Planner]

Central government, since they're funding electrification.

No, they are funding electrification, not capacity enhancements to stations. Unless that is part of the scheme, no one is coughing up for it.

 

[455driver]

the Desiros have UDS - Unit Deselect

Utterly stupid/useless system if you ask me, but what do I know

Quite agree, Fareham on the down is an 8 coach platform but when a 12 coach 450 stops there the guard has to open the front 4 only because the cab door on the 9th coach (where the guard would need to be to open 8 coaches up) is off the platform.

Bonkers, ill thought out (read that as cheap) system.

 

[Crossover]

Quite agree, Fareham on the down is an 8 coach platform but when a 12 coach 450 stops there the guard has to open the front 4 only because the cab door on the 9th coach (where the guard would need to be to open 8 coaches up) is off the platform.

Bonkers, ill thought out (read that as cheap) system.

Why can't the 8 coaches be unlocked from the rear cab of the sandwiched unit? Or is the system even worse thought out than first thought?

 

[455driver]

Because the guard can only use the SDO switch in the front cab of the unit he wants to de-select, in this case it is the front cab of the rear unit, ie 9th coach.

Hilsea on the up is the same.

 

[Crossover]

So it is very useless then?

 

[Monty]

So it is very useless then?

The SDO/UDS feature on the Desiro's is pretty basic and as 455driver has mentioned you need to be in the leading cab of the unit you wish to lock out. I wouldn't say it's completely useless though, it does pose issues with 444s at LDO (local door opening) stops. When ASDO is rolled out over the course of the next couple of years it should make things a bit easier.

 

[Muzer]

Quite agree, Fareham on the down is an 8 coach platform but when a 12 coach 450 stops there the guard has to open the front 4 only because the cab door on the 9th coach (where the guard would need to be to open 8 coaches up) is off the platform.

Bonkers, ill thought out (read that as cheap) system.

As I said, worse at Shawford, there's no way they can even open more than one door at the moment!

 

[the sniper]

So it is very useless then?

I don't know if it's the same on 450s, but it gets worse on 350/1s. The only way to know if the UDS is 'on' after turning the switch is to pick up the handset and wait to listen for the 'please move forward...' announcement. If you don't hear it/ it doesn't play before you get to the station, officially you can't open any of the doors and have to go on to the next stop. The switch lights up on 350/2s...

Is SDO/UDS a phenomenon not known to the Germans? I can't understand how Siemens screwed up so badly on this front.

 

[johnb]

Is SDO/UDS a phenomenon not known to the Germans? I can't understand how Siemens screwed up so badly on this front.

Another thread mentions that Siemens prepared for the SWT Desiro order by testing the hell out of a VEP, for which SDO would be irrelevant. With the SWT fleet at the time of the order all either slam-door or 455s without SDO, I wonder if simply nobody at either SWT or Siemens gave the issue any thought, until far too late in the process for a complex SDO system to be shoehorned in?

 

[Matt Taylor]

Because the guard can only use the SDO switch in the front cab of the unit he wants to de-select, in this case it is the front cab of the rear unit, ie 9th coach.

Hilsea on the up is the same.

This info is out of date, during last summer the starter signal at Fareham was moved a couple of yards so that on a 12 car set the front 8 can be opened as normal. Hilsea remains a peculiarity in that it 8 coaches that can be opened on an 8 car set but only 4 if it's a 12 car set-on both up and down lines.

It is a horrendous system, when working a 12 car set from Portsmouth to London via Eastleigh you can have up to 9 consecutive SDO stops with the following coach lengths: 8-4-8-4-8-4-8-8-4 so that's a lot of running up and down the train.

 

[craigwilson]

I don't know if it's the same on 450s, but it gets worse on 350/1s. The only way to know if the UDS is 'on' after turning the switch is to pick up the handset and wait to listen for the 'please move forward...' announcement. If you don't hear it/ it doesn't play before you get to the station, officially you can't open any of the doors and have to go on to the next stop. The switch lights up on 350/2s...

Is SDO/UDS a phenomenon not known to the Germans? I can't understand how Siemens screwed up so badly on this front.

It sounds completely useless to me....

The two types of stock that I regularly use in Kent seem to have "proper" SDO i.e. it seems that both on the 375s and 395s working in multiple, the driver can open however many doors are needed, for example, front 10 at Rochester on a 12-car (3 x 375). I've additionally seen them open the front 8 only on a doubled-up 395 at Canterbury.

I've no idea how the SDO works on these two classes that is different from the Desiros, other than that the driver controls door opening, not the guard/train manager.

I've very little experience of Networkers (and not at all in multiple) so I can't speak for them.

 

[Matt Taylor]

The 377s use ASDO which is what the SWT Desiros will soon be using, 375s are probably the same.

 

[yorksrob]

Whenever I go past a station undergoing platform lengthening, it always appears to be a fairly heavy duty bit of building work.

What seems to be needed is a relatively cheap and straight forward modular platform extension similar perhaps to the concrete harps and slabs that are still found around the Southern Region. If this sort of kit existed, it might lower costs and allow lengthening to take place more easily alongside other enhancements.

They could also use them to throw up new halts relatively quickly.

 

[asylumxl]

Whenever I go past a station undergoing platform lengthening, it always appears to be a fairly heavy duty bit of building work.

What seems to be needed is a relatively cheap and straight forward modular platform extension similar perhaps to the concrete harps and slabs that are still found around the Southern Region. If this sort of kit existed, it might lower costs and allow lengthening to take place more easily alongside other enhancements.

They could also use them to throw up new halts relatively quickly.

Such a system exists and was used at Elstree and Borehamwood to extend platforms to 12 carriages.

http://www.youtube.com/watch?v=eXg1NtihCNI

 

[yorksrob]

Such a system exists and was used at Elstree and Borehamwood to extend platforms to 12 carriages.

Hopefully we'll see a load more in that case.

 

[asylumxl]

Hopefully we'll see a load more in that case.

We can hope!

 

[jopsuk]

The Class 222 seem to have quite a simple system - though the driver works it -where the number of carriages to be opened is selected with a button push, with the number displayed at the stop marker on the platform