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GWR to lease ‘tri-mode’ class 769 multiple units from Porterbrook


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Presumably the railways are subject to the electricity at work regulations?

 

I think that Pt.II regulation 14 of those regulations is worth quoting:

 

14. No person shall be engaged in any work activity on or so near any live conductor (other than one suitably covered with insulating material so as to prevent danger) that danger may arise unless–

 

(a)

 

it is unreasonable in all the circumstances for it to be dead; and

.

 

(b)

 

it is reasonable in all the circumstances for him to be at work on or near it while it is live; and

.

 

©

 

suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

 

When I was a senior authorised person in electricity generation preparing and issuing permits to work that was pretty much the prime commandment for electrical work alongside our safety rules.

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Going back to the calls for infill electrification along the North Downs route... 

 

If we're ruling out 3rd rail infill, what would be the downsides to doing the infills as 25kV overheads? There are already many dual-voltage EMUs out there, the 319/769s for one, so the rolling stock doesn't seem to be a problem.

I know, NR has made a hash of recent electrification schemes, but assuming a competent installation team, what would be the technical downsides?

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Doing the infills with 25kV would require a disproportionate number of feeder stations, which are by far the biggest expense on any electrification scheme. Having both 25kV and 3rd rail between Ash and Shalford would reduce that, but interfaces between 3rd rail and 25kV are a world of pain and another money pit, and an infill on the north downs line would have 4 such interfaces. It would be madness to do it like that. Overhead DC would be more feasible (And actually a few 750/ 3kV 450s might actually be a possibility) but I wouldn't hold my breath for that to happen.

It would be more feasible on the Uckfield line as the only real interface would be at Hurst Green, but you'd still need 2 feeder stations (for redundancy purposes) which would cost far too much for a little branch like that.

Lines like those are actually ideal for bi modes. It's using bi mode technology as an excuse to not electrify into Bristol that I object to...

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Presumably the railways are subject to the electricity at work regulations?

 

I think that Pt.II regulation 14 of those regulations is worth quoting:

 

14. No person shall be engaged in any work activity on or so near any live conductor (other than one suitably covered with insulating material so as to prevent danger) that danger may arise unless–

 

(a)

 

it is unreasonable in all the circumstances for it to be dead; and

.

 

(b)

 

it is reasonable in all the circumstances for him to be at work on or near it while it is live; and

.

 

©

 

suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

 

When I was a senior authorised person in electricity generation preparing and issuing permits to work that was pretty much the prime commandment for electrical work alongside our safety rules.

 

Plenty of scope there for interpretation of the words "unreasonable and reasonable", I would have thought.

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Going back to the calls for infill electrification along the North Downs route... 

 

If we're ruling out 3rd rail infill, what would be the downsides to doing the infills as 25kV overheads? There are already many dual-voltage EMUs out there, the 319/769s for one, so the rolling stock doesn't seem to be a problem.

I know, NR has made a hash of recent electrification schemes, but assuming a competent installation team, what would be the technical downsides?

It is probably fairer to say that the ongoing saga that is one particular electrification scheme has monopolised opinions of electrification in the UK. It may not be total sweetness and light on the other schemes that are in progress or recently completed, but they have been going on without all the setbacks of Great Western.

 

Jim

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I am a bit curious as to how we ended up with so much of it in the first place. I appreciate that views on acceptable safety have changed dramatically over the years, but have the operational issues also become more of a problem?

It has a lot to do with both the technology of its time and, until the extensions to Brighton and Portsmouth, the system essentially being a suburban electrification. Until the advent of rectifiers that could be carried on board trains, AC traction was a lot more difficult than DC, and with the densities of trains involved, using DC and putting all the heavy expensive equipment in the substations made economic sense. The LBSCR's AC electrification was way ahead of its time, but it was intended as the first stage of longer distance electrification, when it would have made sense.

The problem is that once the Southern Railway had cast the die in favour of DC, and started to create a dense suburban network, it was effectively stuck with it. Electrifying to Brighton and Portsmouth might have been all very well, but over the distances involved there are a lot of substations, not to mention a considerable AC distribution network just to supply them, for a relatively low number of trains. It's not the way it would be done now, but we have to live with the legacies of the past, not just in the technology but also the limitations of the structures.

 

In terms of safety, attitudes have changed over the years. Practices that were considered acceptable into the 1950s, if not significantly beyond, are no longer acceptable in a society that is a lot stricter in regard to the health and safety of the workforce. If the railway was being electrified with exposed conductor rail now, it would be in contravention of the Electricity at Work Regulations and would simplt not be permitted. The problem is that the conductor rail is already there, in considerable quantities and replacing it with something else is simply beyond the bounds of that which is reasonably practicable; it is tolerated by the safety authority, but every reasonable effort is expected to be made to achieve greater degree of compliance over the long term. Achieving that is going to require a greater degree of cooperation and thinking between the different engineering disciplines that are involved in creating and maintaining an electric railway, something that is not currently conspicuous by its presence. The DC third-rail railway is no longer a steam railway onto which electrification can be added after everything else has been designed; track and signalling design has to be undertaken hand in hand with electrification design before equipment goes on the ground, not as an afterthought.

 

Jim

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Back to the actual subject of the OP - the Class 769.

 

This is all a result of the decision for GWR to operate the Heathrow Express services using a number of the existing Class 387 Fleet.

 

The 769s will replace the Turbos, the Turbos will release 387s for conversion. When 2x 387s are converted they will take over from the current HEX units.

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I don't have all the figures but it seems strange that this is a better option than a fill-in electrification of the North Downs line.

 

Installing third-rail electrification on the whole of the North Downs would be the sensible thing to do.  The only parts that don't have the third rail are North Camp to Wokingham and the steeply graded section from Reigate to Shalford Junction.  The line is heavily used both by commuters and passengers go to and from Gatwick airport - a very different picture from many years ago when the line was threatened with closure. Unfortunately sense may not come into it now, on two accounts: overhead electrification is now to be preferred instead of third rail (and hence expensive) and therefore there will be no further electrification in the foreseeable future.  Putting four-coach trains on will be helpful but I rather like the present class 165s - comfortable and relatively quiet for underfloor mounted diesel engines, especially in comparison with the awful Cross Country Voyagers.

Peterfgf

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The Brighton Main Line (part of it) gets 319's (all be it reheated and given a coat of paint) back once again.  That probably won't be overly popular in some areas although probably more welcome than the 700's that replaced them in the first place.

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It is probably fairer to say that the ongoing saga that is one particular electrification scheme has monopolised opinions of electrification in the UK. It may not be total sweetness and light on the other schemes that are in progress or recently completed, but they have been going on without all the setbacks of Great Western.

 

Jim

Fair point, although the work in the NW seems to be late as well.

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foreseeable future.  Putting four-coach trains on will be helpful but I rather like the present class 165s - comfortable and relatively quiet for underfloor mounted diesel engines, especially in comparison with the awful Cross Country Voyagers.

 

The 165s have decently sized windows too, that mostly line up with the seats.

 

The last time I went on a Voyager I was paying attention to engine sound (because I'd just been on an IET and was impressed how quiet the engines were on that) and I realised that I could barely hear the engines on the Voyager either.

 

(Maybe they'd failed in the coach I was in?)

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In most DMUs it depends where you are in relation to the engine. In a 158 they can be loud and intrusive if you're sitting on top of them, but if you're over the fuel tank it's more of a distant hum. The same with 150s though they're louder pretty much all the time.

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In most DMUs it depends where you are in relation to the engine. In a 158 they can be loud and intrusive if you're sitting on top of them, but if you're over the fuel tank it's more of a distant hum. The same with 150s though they're louder pretty much all the time.

 

In a 158 it makes a big difference. I've not really been aware of much difference on other trains though (apart from DEMUs with above-floor engines).

 

I have a vague memory that it's not actually the engine on a 158 making the most noise.

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The 165s have decently sized windows too, that mostly line up with the seats.

 

The last time I went on a Voyager I was paying attention to engine sound (because I'd just been on an IET and was impressed how quiet the engines were on that) and I realised that I could barely hear the engines on the Voyager either.

 

(Maybe they'd failed in the coach I was in?)

 

I expect the engine had failed - having recently made two trips of c.5 hours in Voyagers I was acutely aware of the engine noise and occasional vibration, impossible to have a really quiet conversation with Mrs Stationmaster sitting opposite me.  and their susceptibility to rough riding on bits of track which don't suit them hasn't gone away either.

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I expect the engine had failed - having recently made two trips of c.5 hours in Voyagers I was acutely aware of the engine noise and occasional vibration, impossible to have a really quiet conversation with Mrs Stationmaster sitting opposite me.  and their susceptibility to rough riding on bits of track which don't suit them hasn't gone away either.

 

I find them to be fairly quiet at higher speed...

 

Anyway on the subject of Class 769s, the news has caused much excitement in the world of APCO, so I might be designing for these things as well!

 

Simon

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I expect the engine had failed - having recently made two trips of c.5 hours in Voyagers I was acutely aware of the engine noise and occasional vibration, impossible to have a really quiet conversation with Mrs Stationmaster sitting opposite me.  and their susceptibility to rough riding on bits of track which don't suit them hasn't gone away either.

 

It's not unknown for Cross Country Voyagers (particularly 221s) to run with one engine shut down for fuel saving.

 

Cheers,

Mick

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Because of the safety precautions required when undertaking track work in 3rd rail areas, the cost-per-mile of maintenance is greater than for non-electrified or overhead electrified territory.

 

The DfT's past record suggests a greater emphasis on saving money than saving lives and I suspect that cash is the dominant reason for hostility to creating any more of it.

 

John

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Engines can be silenced and isolated from their surroundings very effectively if the money if there. Most of the options available to uncouple engine vibration from whatever its mounted to are pretty mature and technically straightforward and can be extremely effective, particularly if you add active techniques into the mix. The problem is they're not cheap (people tend to think that straightforward = cheap) and if people are reluctant to spend then it is an easy part of a specification to dilute. I've worked on naval projects where engine and machinery noise was suppressed to a remarkable degree.

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The 769's are now rumoured to be set to replace the Southern 171's on the Uckfield and Ashford/Hastings routes.

 

I can't see that happening somehow, the Uckfield Line commuters would be most displeased for a starter.

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1 hour ago, John M Upton said:

 

I can't see that happening somehow, the Uckfield Line commuters would be most displeased for a starter.

 

I can

 

The 171s have a significantly worse acceleration rate than EMUs - and given the congested nature of the BML from South Croydon inwards every second counts! The Uckfield line having single line sections and passing loops also means that time keeping i/ recovering late running on the 3rd rail bits is important to avoid late running being made considerably worse.  Bi - modes, which can match the 377s / 700s north of Hurst Green would thus help considerably.

 

Its also reported by those that have to look after the things that the ex Scotrail 170 to 171 conversions are still well below par as far as reliability goes frequently leaving Selhurst struggling to provide enough units for peak time services.

 

Similarly the Eastbourne to Ore section of the Marshlink service has conductor rail, and while less busy than the BML through south London, the ability to use 3rd rail power is an environmentally sensible move. The bigger advantage though is the ability to have a larger fleet of trains. The problems with pathing the diesel worked 171s means its not viable to have more than the bare minimum on the books - so when one unit goes down services have to be cancelled. If a large fleet of Bi-modes were procured then you could use some of them as straight electrics (just as not all of Southern's dual voltage 377s are used under overheads), thus providing a greater pool of spare units potentially preventing Marshlink cancellations.

 

Finally, the main reason the Marshlink got cut back to Eastbourne from Brighton was the large numbers of passengers from Brighton to Lewes / Eastbourne using the service because of its 'express' nature compared to most other services. Timing the Marshlink back to Eastbourne allowed a 4 car electric unit to be put on the 'express' leg thus providing more accommodation for passengers. The introduction of 4 car bi-modes on the likes of the Marshlink could allow the return of through services to Brighton .

 

 

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In sure they'd be better than 171s, but 319s weren't exactly known for their acceleration, and the added weight of the diesel engines won't help much. Unless the whole traction package is being changed (in which case they probably might as well just buy some flirts)

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4 hours ago, John M Upton said:

The 769's are now rumoured to be set to replace the Southern 171's on the Uckfield and Ashford/Hastings routes.

 

I can't see that happening somehow, the Uckfield Line commuters would be most displeased for a starter.

 

As far as I'm aware 319s remain banned from Oxted Tunnel, so I think that's one rumour easily debunked.

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