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Class 175s to GWR

stevieinselby

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185's wouldn't be much good for the West, they're much heavier than anything we currently have and they guzzle fuel.
The obvious deployment for them in GWR territory would be on the mainline, where they have been using the Castle sets, and where the extra power will give some benefits – there aren't any restrictions that would limit the 185 to a lower speed than the Castles, which are considerably heavier (per vehicle). It would be mad to use them on the branch lines.
I wonder what the weight of a GWR battery 230 is compared to a 150 and a 150 becomes lighter as it uses fuel.
A more relevant comparison would be the GWR 230 with a TfW 230 – battery and diesel alternatives of the same platform.
While a diesel train will burn fuel over the course of the day, a diesel engine itself is a big heavy lump of metal and weighs considerably more than the equivalent electric motor.
According to a recent interview featured on Green Signals, a BEMU will weigh about the same as a comparable DMU, although they don't specify whether that is full of fuel or not!
Yes the South West seems to be getting lots of stop gaps
165s displaced from London Suburban by 345s
166s displaced from Thames Valley by 387s
175s displaced from Wales by 197s
Potentially 185s from Transpennine

Not really a long term strategy
No reason why using cascaded units can't be a long-term strategy, if there's going to be a steady supply of them as mid-life trains are replaced in other areas.
Where you have a part of the network that has quieter branch lines, it may be perfectly sensible to channel the investment in new trains into other areas where there is more potential to attract passengers and you will get more bang for your buck. You also want to put that investment into routes where the trains can live up to their potential, and low speed branch lines where passengers are making short journeys are a more appropriate deployment for older trains that are getting a bit tired than for brand new state-of-the-art trains.
 
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Western Sunset

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There is nothing wrong, per se, in using cascaded units. The critical proviso is that in the interim between one TOC and another, the units are stored correctly with a little TLC. Not left in the middle of nowhere to sit and rot.
 
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Since 230s have been mentioned - GWR have been employing one quite successfully on the Greenford branch, albeit on Saturdays only. I imagine they're totally unsuitable for the West Country, however getting more 230s going on the Thames Valley branches would free up some DMUs for a cascade?
 

DelW

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Since 230s have been mentioned - GWR have been employing one quite successfully on the Greenford branch, albeit on Saturdays only. I imagine they're totally unsuitable for the West Country, however getting more 230s going on the Thames Valley branches would free up some DMUs for a cascade?
There is a separate GWR Class 230 thread in this forum ....

I believe GWR ruled out any further conversions of D78s, or even recommissioning of the ex Marston Vale diesel units, quite some time ago. Though AIUI both those 230s, and the unconverted D78s, remain in storage.
 

REVUpminster

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003 looks like the only one out today. Newquay's second train was cancelled today although a 150 has come down to replace it attached to a 158 as far as Par. Seeing that I wonder why that can't be used at Barnstaple for the 0732 instead of supplementary buses. They intend to use the 175 as 3+2 on that train and havel a "novel" way of doing it.
 

RPI

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003 looks like the only one out today. Newquay's second train was cancelled today although a 150 has come down to replace it attached to a 158 as far as Par. Seeing that I wonder why that can't be used at Barnstaple for the 0732 instead of supplementary buses. They intend to use the 175 as 3+2 on that train and havel a "novel" way of doing it.
The 07:32 is a 4 car 150 already (most of the time), you can't run anymore than that without SDO or locking coaches out
 

REVUpminster

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The 07:32 is a 4 car 150 already (most of the time), you can't run anymore than that without SDO or locking coaches out
Well that is the "novel" way 175s will work. One unit will fill up at Barnstaple with Exeter passengers; lock the unit and the guard travel in the other unit for the short platform stations.
 

RPI

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Well that is the "novel" way 175s will work. One unit will fill up at Barnstaple with Exeter passengers; lock the unit and the guard travel in the other unit for the short platform stations.
Yes, I'm fully aware, but your post suggested that the unit that's on its way to Par be utilised for the Barnstaple , that's how I read it
 

Kentish RYS

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Well that is the "novel" way 175s will work. One unit will fill up at Barnstaple with Exeter passengers; lock the unit and the guard travel in the other unit for the short platform stations.
A question on the door lock out in 150s, versus 175s, do the 150s have an older can't be used even in emergency lock out and the 175s have a newer type that still allows emergency exit?

And is the reasons they are not running more than 4 car 150s due to lack of more units or 6 cars too long for somewhere or something else?
 

Snow1964

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The 07:32 is a 4 car 150 already (most of the time), you can't run anymore than that without SDO or locking coaches out
A question on the door lock out in 150s, versus 175s, do the 150s have an older can't be used even in emergency lock out and the 175s have a newer type that still allows emergency exit?
If it helps, these are platform lengths from sectional appendix, a pair of 2car 175s is 95m long vs 80m for pair of 150s

route 606 (Barnstaple) and 608 Oakhampton (pages 251-257)

Newton St Cyres platform 120m
Crediton down plat 135m, up 155m
Yeoford Barnstaple platform 136m, Oakhampton plat out of use
Oakhampton Interchange 100m
Oakhampton platform 3 123m

Copplestone platform 87m
Morchard Road platform 90m
Lapford platform 81m
Eggesford down plat 85m, up plat 92m
Kings Nympton platform 90m
Portsmouth Arms platform 74m
Umberleigh 139m
Chapleton platform 100m
Barnstaple platform 142m

And is the reasons they are not running more than 4 car 150s due to lack of more units or 6 cars too long for somewhere or something else?
Generally too long, Athough could operate 6 car 150 on Oakhampton line (except the new Interchange whose platform is shorter than others), but more realistically GWR is short of usable DMUs, with regular short forms so not likely to run triple sets
 

Ashley Hill

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A question on the door lock out in 150s, versus 175s, do the 150s have an older can't be used even in emergency lock out and the 175s have a newer type that still allows emergency exit?

And is the reasons they are not running more than 4 car 150s due to lack of more units or 6 cars too long for somewhere or something else?
GWR 150s/158s have no lock out or any SDO. It’s all doors open where trains fit or local door only where they don’t. The majority of stations will take a 4 car 150 with only Newton St Cyres (and Lapford in the up direction) requiring local door operation. A six car formation will require local door operation at nearly all stations. This will slow boarding/alighting considerably and is not really practical.
 

Lurcheroo

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A question on the door lock out in 150s, versus 175s, do the 150s have an older can't be used even in emergency lock out and the 175s have a newer type that still allows emergency exit?

And is the reasons they are not running more than 4 car 150s due to lack of more units or 6 cars too long for somewhere or something else?
To lock a 150 door essentially means rendering the door unusable by locking it out of use. Locking all the doors on 2 carriages and then allowing passengers to travel in them is not permitted.

175’s have a switch called ‘TUDI’ which means 2nd unit door isolation. Given the context, if a 3+2 stops at a 4 car platform, the conductor can operate the TUDI switch in the rear cab of the front unit which, when the guard releases the door locking, will not unlock the doors on the 2 car unit (of which one carriage won’t be platformed), but will unlock the doors on the 3 car unit (which will all be platformed).

I would not be surprised if there is some contention regarding the fact that the conductor must be in the front unit for this to work, leaving the rear unit unstaffed.
 

XFeed

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A question on the door lock out in 150s, versus 175s, do the 150s have an older can't be used even in emergency lock out and the 175s have a newer type that still allows emergency exit?

Lurcheroo has answered your question by referring to the TUDI switch - Trailing Unit Door Isolation - and if the situation ever arose with a staff member travelling in the trailing unit and they had to exit the train in an emergency then the internal green egress handle would work normally to manually open the bodyside door below 5mph but there is one situation that the egress handle will not open the bodyside door manually and that is if an individual door is locked out of use in the door header panel, also in this situation the green external access handle will not work either.
 

REVUpminster

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To lock a 150 door essentially means rendering the door unusable by locking it out of use. Locking all the doors on 2 carriages and then allowing passengers to travel in them is not permitted.

175’s have a switch called ‘TUDI’ which means 2nd unit door isolation. Given the context, if a 3+2 stops at a 4 car platform, the conductor can operate the TUDI switch in the rear cab of the front unit which, when the guard releases the door locking, will not unlock the doors on the 2 car unit (of which one carriage won’t be platformed), but will unlock the doors on the 3 car unit (which will all be platformed).

I would not be surprised if there is some contention regarding the fact that the conductor must be in the front unit for this to work, leaving the rear unit unstaffed.
I appreciate the answer how it would work with 175s but as to a unit being unstaffed; didn't this happen with 143+150s so each train had an accessible toilet although Saturday mornings there was the often the guard selling tickets in one unit and a ticket inspector selling tickets in the other unit. Paignton on Saturdays had the ticket office open, inspectors selling tickets on the door to the platform who would then often get on the train.
 

RPI

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To lock out doors on a 150 means locking the coach out of use, this is because the doors are physically locked and can't be opened even in an emergency (without a carriage key), 158's I think can have the rear door locked on the "flag" as used to happen at Eggesford and Dockyard, but I'm not sure whether this is still the case, @Ashley Hill will know the definitive answer to this.

As for having two members of staff in a double 175, I believe this conversation is ongoing, it wasn't a requirement when 143's, 150/1's etc were in service, but things may have changed.
 

craigybagel

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To lock a 150 door essentially means rendering the door unusable by locking it out of use. Locking all the doors on 2 carriages and then allowing passengers to travel in them is not permitted.

175’s have a switch called ‘TUDI’ which means 2nd unit door isolation. Given the context, if a 3+2 stops at a 4 car platform, the conductor can operate the TUDI switch in the rear cab of the front unit which, when the guard releases the door locking, will not unlock the doors on the 2 car unit (of which one carriage won’t be platformed), but will unlock the doors on the 3 car unit (which will all be platformed).

I would not be surprised if there is some contention regarding the fact that the conductor must be in the front unit for this to work, leaving the rear unit unstaffed.
Although time consuming, the guard can travel in the front cab of the trailing unit. On arrival at the short platformed station, they can use the platform to move to the trailing cab of the front unit, turn the TUDI switch, and operate the doors from there. They can then close from there, reset the TUDI switch, then make their way back to the trailing unit front cab to give the right away.

This was actually a recommended, but rarely used, method of despatch at TfW.
 

Ashley Hill

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To lock out doors on a 150 means locking the coach out of use, this is because the doors are physically locked and can't be opened even in an emergency (without a carriage key), 158's I think can have the rear door locked on the "flag" as used to happen at Eggesford and Dockyard, but I'm not sure whether this is still the case, @Ashley Hill will know the definitive answer to this.
A defective door on a 150/158 can be locked OOU and the passengers remain as long as it’s not an end door.
The routine locking of end doors at pre- extension Eggesford happened but I don’t think it was officially sanctioned. The risk was forgetting to unlock it after departure. The practice does not happen anywhere now.
 

RPI

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A defective door on a 150/158 can be locked OOU and the passengers remain as long as it’s not an end door.
The routine locking of end doors at pre- extension Eggesford happened but I don’t think it was officially sanctioned. The risk was forgetting to unlock it after departure. The practice does not happen anywhere now.
Thanks for that, my point regarding 150's would be that if a whole coach was locked out, ie every door, then passengers couldn't travel in it, is that right?
 

Snow1964

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175’s have a switch called ‘TUDI’ which means 2nd unit door isolation. Given the context, if a 3+2 stops at a 4 car platform, the conductor can operate the TUDI switch in the rear cab of the front unit which, when the guard releases the door locking, will not unlock the doors on the 2 car unit (of which one carriage won’t be platformed), but will unlock the doors on the 3 car unit (which will all be platformed).
Of course can also get the situation where it is 2+3 (not 3+2) which is not great as get doors opened on only 2 of 4 platformed vehicles in this example, even though only 5th vehicle doesn't have a platform.
I appreciate the answer how it would work with 175s but as to a unit being unstaffed; didn't this happen with 143+150s so each train had an accessible toilet although Saturday mornings there was the often the guard selling tickets in one unit and a ticket inspector selling tickets in the other unit. Paignton on Saturdays had the ticket office open, inspectors selling tickets on the door to the platform who would then often get on the train.
GWR has some 4 and 5 car workings calling at Avoncliff (where platform is front door only) where there is no through gangway on 165 & 166 units. Staff seem to move to front unit at previous station, leaving rear unit unstaffed, then swap back at following station.
As for having two members of staff in a double 175, I believe this conversation is ongoing, it wasn't a requirement when 143's, 150/1's etc were in service, but things may have changed.
This isn't a historic concept though, it is still in use by GWR at Avoncliff, and to be honest if 165s with no through gangway are acceptable, why would a 175 need to be treated differently (they are both DMUs, just built about 10 years apart, about 26 and 36 years ago)
 

Ashley Hill

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Thanks for that, my point regarding 150's would be that if a whole coach was locked out, ie every door, then passengers couldn't travel in it, is that right?
Correct.

== Doublepost prevention - post automatically merged: ==

This isn't a historic concept though, it is still in use by GWR at Avoncliff, and to be honest if 165s with no through gangway are acceptable, why would a 175 need to be treated differently (they are both DMUs, just built about 10 years apart, about 26 and 36 years ago)
At Avoncliff the services have previously stopped at either Bradford-on-Avon or Freshford so the passengers are only in an unlocked portion of a train for a few minutes and all doors are available at all other stations.On a 5 car 175 the rear two cars would have passengers locked in it from Barnstaple to Crediton or potentially Exeter SD if stopping at Newton St Cyres.
 
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Jrocks

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Think what people are forgetting with the 143/150 combos (and the same for turbo combos in the Bristol area) is that none of the train was ever 'locked out'. Yes the Conductor was in the front set sometimes, but the rear set was never locked - in essence if the conductor really wanted to they could release all doors and all doors would unlock!

On a double 175, the rear set in essence becomes locked with the TUDI switch, so you are then locking passengers in the rear set with no staff. Yes, there is more to it than that, but that's the simple thinking. And yes, if the passengers pulled the Egress they could get out, but the conductor couldn't just go to the nearest panel in the front set and release all doors, they would have to ensure the rear set is 'unlocked' through the TUDI switch beforehand.

If the TUDI switch wasnt a thing and we could operate in multiple with all coaches being accommodated at all platforms, i dont see there being an issue with where the conductor was located - see double set turbos working in the Bristol area, these dont have rules or obligations regarding the conductor must be in the rear set.
 

REVUpminster

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I found the quote in Modern Railways September issue page 53/54 of In Focus Great western. Mark Hopwood interview.

Tarka Potential......... "More immediately the plan is that class 175's will take over more services on this route when they become available. Unlike the class 158s used on the branch today '175s' do not have gangway connections joining units. GWR has devised a novel method of operation which will allow two class 175s to be used in multiple on the branch under the control of one conductor. The principal flows on the branch originate at Barnstaple and Crediton, so the leading unit would be reserved for passengers using these stations and the doors on this unit would remain closed at smaller stops. The conductor would travel in the rear unit opening the doors at the back of the train at intermediate stations"

So I presume using the methods used in previous posts by people who know far better than me.
 

Snow1964

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I found the quote in Modern Railways September issue page 53/54 of In Focus Great western. Mark Hopwood interview.

Tarka Potential......... "More immediately the plan is that class 175's will take over more services on this route when they become available. Unlike the class 158s used on the branch today '175s' do not have gangway connections joining units. GWR has devised a novel method of operation which will allow two class 175s to be used in multiple on the branch under the control of one conductor. The principal flows on the branch originate at Barnstaple and Crediton, so the leading unit would be reserved for passengers using these stations and the doors on this unit would remain closed at smaller stops. The conductor would travel in the rear unit opening the doors at the back of the train at intermediate stations"

So I presume using the methods used in previous posts by people who know far better than me.
This sounds like 4 and 5 (and possibly 6) car class 175 stop boards will be beyond the forward end of the platform, so the rear cars will be in the platform when stopped.

I am sure there are other stations where car stop markers for longer trains are beyond the platform, from memory IETs at Thatcham do it
 

Roylang

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This sounds like 4 and 5 (and possibly 6) car class 175 stop boards will be beyond the forward end of the platform, so the rear cars will be in the platform when stopped.

I am sure there are other stations where car stop markers for longer trains are beyond the platform, from memory IETs at Thatcham do it
Hayle in the down direction has stop boards way off the end of the platform and on the viaduct.

Roy
 

REVUpminster

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003 passenger as3C01. 114+011 on Paignton mileage accumulation/training. 2C05 was done by a 150.

114+011 spends over an hour in Plymouth Dk3. Meal relief?
 

The exile

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This sounds like 4 and 5 (and possibly 6) car class 175 stop boards will be beyond the forward end of the platform, so the rear cars will be in the platform when stopped.

I am sure there are other stations where car stop markers for longer trains are beyond the platform, from memory IETs at Thatcham do it
Even Bath Spa!
 

Ashley Hill

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This sounds like 4 and 5 (and possibly 6) car class 175 stop boards will be beyond the forward end of the platform, so the rear cars will be in the platform when stopped.
The conductor would travel in the rear unit opening the doors at the back of the train at intermediate stations"
All the stop boards on the branch are on the ends of the platform so the rear set will always be off.
A similar situation will occur between Plymouth and Liskeard (and vv) when in multiple and stopping at the intermediate stations
 

3RDGEN

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In a double 175, the rear set in essence becomes locked with the TUDI switch
On a 5 car 175 the rear two cars would have passengers locked in it from Barnstaple to Crediton or potentially Exeter SD if stopping at Newton St Cyres.
The rear unit doors are not locked they just don't electrically release, the green egress handle will still mechanically release the door for manual opening in an emergency. The emergency handles allow communication with the driver at all times assuming the units remain coupled.
 
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This sounds like 4 and 5 (and possibly 6) car class 175 stop boards will be beyond the forward end of the platform, so the rear cars will be in the platform when stopped.

I am sure there are other stations where car stop markers for longer trains are beyond the platform, from memory IETs at Thatcham do it
IETs aren't quite the same case though, as they have full SDO.
 

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