GWR Class 800

[swt_passenger]

Does the 800s whilst in diesel mode operate like the class 22*s Diesel engine driving the electric motor that moves the wheels?

To be accurate the diesel engine drives an alternator, and that provides electrical power to drive the motors then yes, but there's a slight difference in that the 22x motors are mounted on the body and have a drive shaft to the bogie, the 80x motors are mounted on the bogies, which is more EMU like...

 

[swt_passenger]

I see, how does the bi mode work is there a point that the pan goes down and the Diesel engines start? Can it be done whilst in motion?

The diesels engines start and are running before the pan goes down. The train coasts during the changeover. It has always been a requirement of the IEP tech spec to be able to change-over while moving, but given the length and age of this thread you could easily have missed the previous times the question has come up...

AIUI trains booked to call at Didcot changeover in the platform, but through trains have a designated area to do the power change at speed; as posted above it's in Moreton Cutting.

 

[59CosG95]

given the length and age of this thread you could easily have missed the previous times the question has come up...

Given that point, do you think it would be a good idea to have a pinned post at the start of the thread, showing all newcomers the facts/figures about the class(es), including method of transmission, units delivered etc.?

 

[swt_passenger]

Given that point, do you think it would be a good idea to have a pinned post at the start of the thread, showing all newcomers the facts/figures about the class(es), including method of transmission, units delivered etc.?

Dunno. Probably be a bit too late now, after 4 years...

 

[59CosG95]

Dunno. Probably be a bit too late now, after 4 years...

Probably. Ah well.

 

[dp21]

I think it would be worth having a pinned post showing the progress of introduction as I'm sure it's a question which will continue to be asked and would save having to hunt for the answers every the time. Similar to the livery threads but just saying which units are in service or being commissioned etc etc.

On another note, looking at the latest reliability statistics, the 800s are now being consistently more reliable than the HSTs. Food for thought/trigger for debate depending who you are.

 

[59CosG95]

I think it would be worth having a pinned post showing the progress of introduction as I'm sure it's a question which will continue to be asked and would save having to hunt for the answers every the time. Similar to the livery threads but just saying which units are in service or being commissioned etc etc.

On another note, looking at the latest reliability statistics, the 800s are now being consistently more reliable than the HSTs. Food for thought/trigger for debate depending who you are.

Indeed, a thread as lengthy as this should probably have a summary post at the front.
Regarding the reliability, it may be that the upward trend of 800s vs HSTs is set to continue, particularly in the wake of 43138's self-consecration at Penzance the other night.

 

[JN114]

The diesels engines start and are running before the pan goes down. The train coasts during the changeover. It has always been a requirement of the IEP tech spec to be able to change-over while moving, but given the length and age of this thread you could easily have missed the previous times the question has come up...

AIUI trains booked to call at Didcot changeover in the platform, but through trains have a designated area to do the power change at speed; as posted above it's in Moreton Cutting.

The engines have a warm up cycle they ideally need to complete before becoming traction powe source. It doesn’t take long; but as such the engines need to be running at changeover.

Specifically on your last point - trains may only pan UP on the move at Moreton Cutting (and Maidenhead East) Where the OHLE has been specially reinforced to accommodate the high forces of panning up at 125mph. The driver can make the transition from Electric to Diesel at any time; but it is done at specific points so that the exact number of miles the GUs have been used for is know for fuel range considerations and so forth.

 

[Chris172]

With pantographs are they constantly pushing on the overhead wires. (Sorry for all the questions, I am a new comer to rail and I find it amazing how they work) plus I doubt I will ever see a class 800 in Birmingham any time soon

 

[JN114]

With pantographs are they constantly pushing on the overhead wires. (Sorry for all the questions, I am a new comer to rail and I find it amazing how they work) plus I doubt I will ever see a class 800 in Birmingham any time soon

Yes - the pantographs are constantly applying pressure to the overhead wires; so that they don’t come off the wires and get tangled and bring wires down.

 

[TwistedMentat]

With pantographs are they constantly pushing on the overhead wires. (Sorry for all the questions, I am a new comer to rail and I find it amazing how they work) plus I doubt I will ever see a class 800 in Birmingham any time soon

If you really want to blow you're mind we know the concept of overhead wires works at least to 574kph. That's the current rail world speed record. https://en.wikipedia.org/wiki/SNCF_TGV_POS#World_rail_speed_record

 

[Domh245]

With pantographs are they constantly pushing on the overhead wires. (Sorry for all the questions, I am a new comer to rail and I find it amazing how they work) plus I doubt I will ever see a class 800 in Birmingham any time soon

Yes, the pantograph is forced upwards to try and keep good contact with the overhead wire, through a combination of mostly spring force (which is actually provided through compressed air I think), and aerodynamic forces. Like @JN114 says it is meant to ensure that they don't come off the wires, which means that you don't get arcing which can damage the pantograph and the wires. If you watch videos of (for example) Eurostars on HS1, you can see the rear pantograph often sparking like nobody's business which isn't brilliant. It's also partly the reason why the tension of the wires used on the GWML is much higher than previous examples, it helps to reduce the 'bounce' of the wire, which in turn reduces the arcing. When the pantograph is being raised, the force rises upon contact as the upwards acceleration of the pantograph is halted by coming into contact with the wire before then falling back down to normal levels, which is why the areas where you are raising pantographs on the move need extra reinforcement.

If you really want to blow you're mind we know the concept of overhead wires works at least to 574kph. That's the current rail world speed record. https://en.wikipedia.org/wiki/SNCF_TGV_POS#World_rail_speed_record

It puts on quite the light show at that sort of speed, and that was with a significantly higher (near double) tension as well!

 

[Chris172]

Thank you guys for the explanation. GWR should make a daily service to Stourbridge Junction to London Paddington via Worcester offering a nice journey avoiding Birmingham New Street using a class 800/802

 

[Railperf]

With effect from 18/04:

The issue with the Axle Counter at Cholsey has been resolved and IETs in the Down direction can now travel “pans up” from Reading to the normal Power Change Over Point at Moreton Cutting.

This is indeed subject to having a driver signed to run in electric mode. Are there many driver left that are still only signed for 800's in diesel mode only? And how long before they should all be signed for both?

 

[Railperf]

Yes - the pantographs are constantly applying pressure to the overhead wires; so that they don’t come off the wires and get tangled and bring wires down.

How wide a variance is the pressure exerted by the different types of pantograph?

I know on Eurostar - for example, the pantograph is controlled by a selector switch that sets different tension and height settings for Eurotunnel, UK domestic 25KV, French domestic 25KV, French High Speed Lines 25KV, also Belgian 3KV DC and French 1.5KV DC. Some of those settings also limit current draw on the domestic 25KV lines. For example Eurostar sets were limited to 7,000 KW on Uk and French domestic 25KV lines, whereas on HS1 and other high speed lines the power rating was as high as 12,200 KW. The obvious reason being that speeds on the domestic 25KV lines only required 200km/h (125mph).

 

[jimm]

Thank you guys for the explanation. GWR should make a daily service to Stourbridge Junction to London Paddington via Worcester offering a nice journey avoiding Birmingham New Street using a class 800/802

I gather that the idea of some GWR London services reaching Droitwich and Kidderminster is under consideration but that's as far as they would be extended from Worcester - but getting off topic, so let's leave it at that.

 

[D1009]

Thank you guys for the explanation. GWR should make a daily service to Stourbridge Junction to London Paddington via Worcester offering a nice journey avoiding Birmingham New Street using a class 800/802

Don't Stourbridge Jn and Kidderminster already have nicer services from Marylebone?

 

[Harbornite]

Don't Stourbridge Jn and Kidderminster already have nicer services from Marylebone?

Indeed.

http://www.realtimetrains.co.uk/sea...18/04/20/0600-2000?stp=WVS&show=all&order=wtt

 

[jimm]

That would probably depend on whether being on a 20-year-old Class 168 for two-and-half hours floats your boat - give me an 800 any time.

 

[Pete_uk]

I see a 8003XX visited Gloucester the other day. The 9 carriage versions look like propper trains

 

[whhistle]

Given that point, do you think it would be a good idea to have a pinned post at the start of the thread, showing all newcomers the facts/figures about the class(es), including method of transmission, units delivered etc.?

Yes, it's called Wikipedia :P

 

[59CosG95]

To catch up with the delivery side of things, 800019 was delivered today. https://flic.kr/p/JdQfHG

 

[Typhoon_93]

800305 was also delivered from the Aycliffe to Doncaster Friday.

 

[Typhoon_93]

800007 is currently working 5X40 Aycliffe to Doncaster, This set completes Aycliffe’s first build of IEP’s for GWR.

http://www.realtimetrains.co.uk/train/K97568/2018/04/23/advanced

Currently at Aycliffe are:-
800306-310/313 in test.
800314-317 in production.
800318 being delivered.

 

[Thatcham Xing]

trains may only pan UP on the move at Moreton Cutting (and Maidenhead East)

Presumably come the end of the year there will be a similar facility in the Newbury area for up trains to "pan-up"?

 

[JN114]

Presumably come the end of the year there will be a similar facility in the Newbury area for up trains to "pan-up"?

Presumably - there’s been no briefing on the specifics of Newbury Electrification yet.

 

[D1009]

Currently at Aycliffe are:-
800306-310/313 in test.
800314-317 in production.
800318 being delivered.

When you say "being delivered", where to?

 

[Domh245]

When you say "being delivered", where to?

Presumably being delivered to Newton Aycliffe from whichever docks it came in via (I used to think it was Tees docks, but it may be Southampton?)

 

[59CosG95]

Presumably being delivered to Newton Aycliffe from whichever docks it came in via (I used to think it was Tees docks, but it may be Southampton?)

And even then, it's the bodyshells that would be being "delivered", as all the rest of the train is assembled at Newton Aycliffe.

 

[Typhoon_93]

When you say "being delivered", where to?

Sorry should have been more specific 800318 shells being delivered this week from storage at Tees Dock.
All shells arrive at Tees or Tyne Dock but the ones that arrive at Tyne are transferred by road to Hitachi’s huge storage compound at Tees Dock to await the call over to the factory.
The vehicles arriving complete come in via Southampton but this seams to have recently switched to Tees Dock with the arrival of 800201/202 a few weeks back and another as yet unidentified IEP last week that has moved to Doncaster by road.