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Class 175s to GWR

Railperf

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175114 and 175007 working services HSTs did (I might have missed another one). Not a great return on 13 trains at Laira although some may have been cannibalised.
To be fair, from my single trip so far, the 3-car 175 I sampled between Truro and St Erth seemed to cope with passenger numbers. And its performance was barely slower than a short HST. Cornish main line speed limits of no more than 70mph don't require huge amounts of power. I imagine the fuel/maintenance bill will reduce significantly in the longer term.
 
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RailUK Forums

XFeed

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That seems a serious design flaw. How often did that scenario happen when running for TFW?

Dead ducks caused by loss of air were not that frequent and can be caused by a number of varied issues, no 3 phase power for whatever reason the most obvious.

TFW were not keen on keeping 2 car units out in service if one car developed an engine or cooler group fault for the fear of the other car experiencing problems and they then would work it back to us if local or if further afield they would attach it to another unit for return.

Also 3 phase power can be lost to a compressor car by that cars saloon HVAC or vestibule extractor fans developing a fault and tripping that cars main RCD, when this occurs its a pretty easy fix to to regain 3 phase power by isolating the saloon HVAC circuit breaker and resetting that cars main RCD but traincrew often struggle to find the main RCD in the first place and then struggle to reset it.

Its something that they have never been trained for I expect and the first time of them doing it they will probably be on the phone to a Technician.
 

craigybagel

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TMS issues do occur but can be varied reasons depending on the symptoms, TMS will not configure faults usually occur when unit is worked coupled to another unit but 112 wasn`t today also the TMS can display numerous spurious faults continually especially if the unit hasn`t been "Tripped" for more than 24 hrs also if the driver enters a TSN - Train Service Number - at speed and even a slow speed the TMS will spit its dummy out eventually, sometimes straight away but can also be at least an hour later.

Incidentally in our time at Chester the TMS was classed as a driver information system and not a safety system which I found to be totally bizarre !
Indeed I was wondering what the implications of no TMS were now they're at GWR - at TfW you could just trip the MCB, tell the guard that Doris wouldn't work and they'd have to make manual announcements, and then get on with your day.

To be fair though, they didn't contain any safety critical information. It would make further fault finding difficult if anything else went wrong on the day, but not really any different from driving older units that had no TMS at all.
 

Ashley Hill

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Yes you are correct that 175s only have one compressor and that is fitted to the 50 car but its not always game over if there`s an engine or cooler group issue, as Bikeman78 has pointed out, the adjacent car will cross feed 3 phase power across to the affected car and that`s pretty straight forward for a 2 car.

3 cars are slightly more of a problem in regards to cross feeding as cars can only cross feed to adjacent cars so in the scenario of the 56 car engine not running it will be cross fed from either the 50 or 79 cars so if the 50 car then develops an engine or cooler group fault no cross feed to it is available as the 56 car is not running. Its then a dead duck.

Compressors are driven by a 3 phase motor., thanks for the info.
Didn’t know about the cross feed, thanks for the info.
 

Apedlar12

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175114 and 175007 working services HSTs did (I might have missed another one). Not a great return on 13 trains at Laira although some may have been cannibalised.
The other diagram that was 2+4 operated, was 2C11/2P16.

Seems to be an altered timetable for that one this week and is booked for a 150 still instead.
 

coubpro

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Indeed I was wondering what the implications of no TMS were now they're at GWR - at TfW you could just trip the MCB, tell the guard that Doris wouldn't work and they'd have to make manual announcements, and then get on with your day.

To be fair though, they didn't contain any safety critical information. It would make further fault finding difficult if anything else went wrong on the day, but not really any different from driving older units that had no TMS at all.
Yes you are correct that 175s only have one compressor and that is fitted to the 50 car but its not always game over if there`s an engine or cooler group issue, as Bikeman78 has pointed out, the adjacent car will cross feed 3 phase power across to the affected car and that`s pretty straight forward for a 2 car.

3 cars are slightly more of a problem in regards to cross feeding as cars can only cross feed to adjacent cars so in the scenario of the 56 car engine not running it will be cross fed from either the 50 or 79 cars so if the 50 car then develops an engine or cooler group fault no cross feed to it is available as the 56 car is not running. Its then a dead duck.

Compressors are driven by a 3 phase motor., thanks for the info.
Interesting point about older units. In some ways they were simpler because there was less software available to fail or generate nonsense faults in the first place.
 

XFeed

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Didn’t know about the cross feed, thanks for the info.

There are side effects encountered, so to speak, when a car is cross feeding along with the car that is being cross fed. To reduce the load on the cross feeding alternator certain systems are disabled for instance all single phase circuits this includes toilet hand dyers and at seat plug sockets also both cars saloon HVACS run at reduced power.

== Doublepost prevention - post automatically merged: ==

What is the issue with doors?

I was wondering that too, its a pity that we don`t get the reported symptoms with the doors or an individual door and with that information it gives us a stab at the cause.
 
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Russel

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I was wondering that too, its a pity that we don`t get the reported symptoms with the doors or an individual door and with that information it gives us a stab at the cause.

Does seem odd, there has been quite a few mentions of door issues in this thread but there is only so much that can go wrong with a door.
 

XFeed

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Does seem odd, there has been quite a few mentions of door issues in this thread but there is only so much that can go wrong with a door.

There are quite a few things to go wrong with an individual door and even more with the units doors control and safety system but most of the problems encountered are easily fixable and some are also down to Train crew.
 

Russel

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There are quite a few things to go wrong with an individual door and even more with the units doors control and safety system but most of the problems encountered are easily fixable and some are also down to Train crew.

What are the train crew related issues?
 

XFeed

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What are the train crew related issues?

A common one is arming the doors from 2 positions enabled as this destroys the related door enable relays contacts.
If an access or egress handle has been used Train crew can sometimes not reset it correctly.
 

northernbelle

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Back on topic - the first set has received its coat of green at Wolverton. Expected to appear later in the summer.
 

adc82140

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I'm not sure there's yet such a thing as GBR legally speaking, let alone a finalised livery. Aren't all the nationalised former franchises still just DfT Operator Ltd?
 

The exile

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I'm not sure there's yet such a thing as GBR legally speaking, let alone a finalised livery. Aren't all the nationalised former franchises still just DfT Operator Ltd?
Wouldn’t need a “legal” GBR to have a GBR livery. However, the arrangement of deck-chairs is hardly top-priority (or shouldn’t be).
 

northernbelle

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Oh, that's a surprise! All the talk was of them going straight into GBR livery, but clearly not.
Many TOCs are still repainting trains into their existing liveries - Northern, CrossCountry, GWR, SWR to name but a few - all are examples are where trains are due a repaint and the work's been contracted, therefore cannot wait for having a finalised GBR livery that's ready for application to a train (my understanding still a way off).

I suspect with the 175s we'll see a change of livery mid way through the process, given the timescales.
 

St. Paddy

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I'm not sure there's yet such a thing as GBR legally speaking, let alone a finalised livery. Aren't all the nationalised former franchises still just DfT Operator Ltd?
Livery appears finalised as a 387 has been done at Brighton and a GWR IET should emerge from Eastleigh soon
 

northernbelle

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I'm guessing a different shade of green as they obviously are [dark] green right now.
No, they are receiving standard GWR livery until an instruction is received to do otherwise. As it stands the full 800/0 5-car fleet is planned for this treatment.
 

The_Train

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No, they are receiving standard GWR livery until an instruction is received to do otherwise. As it stands the full 800/0 5-car fleet is planned for this treatment.
And why not. An abysmal livery for an abysmal train sounds perfect to me :D
 

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