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GWR Class 800

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samuelmorris

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Has it really?
Without wishing to willy wave have you been in the front cab of one going up hill on diesel power because I have, and I have first hand experience of the full power, slow crawl up the hill!

Or was I mistaken on what I could see with my own eyes and hear with my own ears?

Out of curiosity was that at the 750 setting or the 940 originally reserved for the 802s?
 
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YorkshireBear

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So you are saying I am wrong/blind and/or deaf then.

They do have the same engines but they are set at 700kW not the full 940 so they are a lot (and I do mean a lot) slower than a HST.

There are plans to upgrade them to the full 940kW but as far as I am aware the change to the contracts has not been agreed yet, probably how much more Hitachi are going to charge hasnt been agreed yet.

Have they been uprated since your experience?
 

Clarence Yard

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Don't mix hp with kw! The IET sets on GWR will enter service set at 700kw (940hp), not at the original 565kw. They will also have the larger (1550L) fuel tanks fitted.

The timing runs that were done earlier in the year replicated timetabled moves. This was done to prove to the DfT (and others) that the trains could keep to HST timings overall if they were unmuzzled to 700kw.

On those test runs it was proved the units could do at least 120mph on diesel and still keep to time. Unfamiliarity will obviously play a part in their first few weeks of passenger service but a gradual introduction allows everyone to learn about what these trains will actually do.
 

455driver

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Have they been uprated since your experience?

Not yet, as it is a variation to the specification it has to be agreed who pays for the upgrade and increased maintenance costs over the life of the trains.


Hitachi are rubbing their hands together with all these variations the DaFT keep coming up with.
Has anyone seen what the new leasing charges are?
No thought not, I wonder why?
 

455driver

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Don't mix hp with kw! The IET sets on GWR will enter service set at 700kw (940hp), not at the original 565kw. They will also have the larger (1550L) fuel tanks fitted.

The timing runs that were done earlier in the year replicated timetabled moves. This was done to prove to the DfT (and others) that the trains could keep to HST timings overall if they were unmuzzled to 700kw.

On those test runs it was proved the units could do at least 120mph on diesel and still keep to time. Unfamiliarity will obviously play a part in their first few weeks of passenger service but a gradual introduction allows everyone to learn about what these trains will actually do.

Which hill were they going down to reach 120mph and how long did it take to reach the speed.

My observations are that acceleration from 80mph onwards is rather pedestrian to put it mildly and the slightest hill has the speed falling off very quickly.
 

D1009

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Has it really?
Without wishing to willy wave have you been in the front cab of one going up hill on diesel power because I have, and I have first hand experience of the full power, slow crawl up the hill!

Or was I mistaken on what I could see with my own eyes and hear with my own ears?

So you are saying I am wrong/blind and/or deaf then.

They do have the same engines but they are set at 700kW not the full 940 so they are a lot (and I do mean a lot) slower than a HST.

There are plans to upgrade them to the full 940kW but as far as I am aware the change to the contracts has not been agreed yet, probably how much more Hitachi are going to charge hasnt been agreed yet.
I believe you are very much out of date with this. As I understand it, it is relatively easy (within the depot) to limit them to whatever power you want up to the full 940 hp, and therefore deliver HST performance on diesel. I am quite sure negotiations with Agility Trains on the money side of it are taking place if not finally agreed.
 

455driver

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I believe you are very much out of date with this. As I understand it, it is relatively easy (within the depot) to limit them to whatever power you want up to the full 940 hp, and therefore deliver HST performance on diesel. I am quite sure negotiations with Agility Trains on the money side of it are taking place if not finally agreed.

They can uprate the engines while the train is in service via wifi, or derate it if the mood takes them, unfortunately the radiators on the 700kW ones are smaller than the ones on the 940kW so the 800s eventually overheat due to lack of cooling capacity, thats why it is so expensive to 'uprate' the 800s on a permanent basis, but apparently I am out of date.
 

JN114

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I believe you are very much out of date with this. As I understand it, it is relatively easy (within the depot) to limit them to whatever power you want up to the full 940 hp, and therefore deliver HST performance on diesel. I am quite sure negotiations with Agility Trains on the money side of it are taking place if not finally agreed.

With the correct login credentials it can be done on the TMS on the unit on the fly.
 

SpacePhoenix

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Could the power rating be changed with the use of trackside beacons to signal to the TMS what power rating to use (would assume it would need a slight hardware and software modification)?
 

Pete_uk

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Having seen one up close yesterday, I do admit the initial get away is pretty nippy. Very nippy in fact.

How many axles are powered?
 

JN114

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no it cant

I must have misunderstood what the Hitachi staff was explaining on my first trip on them.

They brought up the power unit status screen on the TMS, and you could tap on the little text box that had the current power rating for the power unit, and it would take you to a screen with a handful of buttons with different power settings on. Tap the one you want and it'd take you back to the status screen, the new value would be in the box.

It was whilst they were running the various trials to see if they could match HSTs on power setting x/y/z - special software version for that purpose not installed on "production" sets? Is there something else in the TMS that I'm confusing this with? Train 3 if it makes any difference, late May.
 

CosherB

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Could the power rating be changed with the use of trackside beacons to signal to the TMS what power rating to use (would assume it would need a slight hardware and software modification)?

What benefit would it bring? That sounds really complicated and expensive to me ......
 

Emblematic

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Twelve on a five car set, as I understand it.

Correct, the driving cars on all sets are unmotored. The intermediate cars are all motored on five car sets, on nine car there are two intermediate trailers, easily identified by their inside-frame bogies. So 20 of 36 motored axles on nine-car sets.
 

deltic08

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Not yet, as it is a variation to the specification it has to be agreed who pays for the upgrade and increased maintenance costs over the life of the trains.


Hitachi are rubbing their hands together with all these variations the DaFT keep coming up with.
Has anyone seen what the new leasing charges are?
No thought not, I wonder why?

How many more miles of electrification could we have for the increase in contract charges and additional diesel consumption over electricity costs?
 

LNW-GW Joint

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How many more miles of electrification could we have for the increase in contract charges and additional diesel consumption over electricity costs?

But it isn't an either/or.
NR blew its budget and timescale, which caused the increased leasing charges.
A triple whammy (incomplete wires, increased operating costs, and other projects cancelled).
 

Wilts Wanderer

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The Class 800s will most certainly be entering passenger service with uprated engine power. With the uprated values, they top out at about 118-120mph, which is just sufficient to keep the HST sectional running times. However I predict they will not quite keep time on the uphill sections, as has been said they seem slightly sluggish uphill. My personal experience was 92mph sustained climbing from Bristol Parkway to Chipping Sodbury, where you'd expect an HST to be comfortably over 100mph. In practice this will drop perhaps a minute against HST schedule but it will be made up by Wootton Bassett Jn, so no real problem. Where I think the train will struggle to keep time is through Box on the Up. My prediction is 1-2 mins net loss against timetable but we will see. Remember the impact of a full load of passengers will change matters. Weirdly it might favour the 800 over the HST because of the bizarre way in which power is managed by the computer.
 

Envoy

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Wonder what GWR are going to name the rest of the fleet?
 

Dave1987

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From what I have been told the main strength of these is low speed acceleration. But when wind resistance starts to really take effect they simply do not have the raw grunt to overcome physics. But hey ho the forum "experts" know best don't they :roll: or maybe they don't :D
 

Dave1987

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Has it really?
Without wishing to willy wave have you been in the front cab of one going up hill on diesel power because I have, and I have first hand experience of the full power, slow crawl up the hill!

Or was I mistaken on what I could see with my own eyes and hear with my own ears?

Wow wow how dare you disagree with the forum "experts"! :lol:

I've been told much the same thing by someone I know who is somewhat involved in the SRT's. Progress is barely keeping up with the traction they are replacing!
 
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Dave1987

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I have zero experience since I'm not a driver as you're fully aware. However they have exactly the same power packs as the 802s so there's no reason to consider them underpowered.

They are currently limited to be pretty much par with HSTs since they are interworking with them for the time being, but they have been shown to be capable of hitting 125mph plus on diesel, and it getting there quicker than a HST would.

really?
 

Dave1987

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Why wouldn't a MU be quicker to accelerate than a HST?

Because and AGAIN this is from someone who is vastly experienced it doesn't matter how much distributed traction you have blah blah blah you can't defy the laws of physics just with distributed traction. You need the full raw grunt once wind resistance starts to take real effect. It's called the laws of physics! I believe a certain person called Roger Ford detailed as much in a column a while ago.
 
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D365

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Ah I didn't see you've already had the discussion about low-end acceleration. No point going round in circles then...

End of the day, no matter what Grayling thinks or says, bi-modes are in no way a solution to the curtailment of mainline electrification.
 
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bonzawe

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5X62, stock movement from Doncaster to North Pole passed Finsbury Park 45 late at 13:05. Has been standing at Holloway ever since. Failed? Reported on Railcam as 802101
 
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deltic08

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But it isn't an either/or.
NR blew its budget and timescale, which caused the increased leasing charges.
A triple whammy (incomplete wires, increased operating costs, and other projects cancelled).

But electrification is continuing to Cardiff and as far as Bath and eventually will reach Bristol via Bath and Parkway as bridge lifting or track lowering is almost complete.

You could say the Government was expecting too much from Network Rail in the first place with their lack of electrification experience. Was unknown signal cable routing the fault of NR? I would say it was the fault of BR or Railtrack.

Who's fault was it that beefed up electrification was ordered for 140mph then cut back to 125mph but more expensive overheads have still been installed.

The only way GWML bimodes can be justified is by cascading them to the MML replaced by all electric IEPs as GWML electrification is completed. That includes completing Cardiff-Swansea and Cheltenham-Gloucester-Swindon.
 

D365

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You could say the Government was expecting too much from Network Rail in the first place with their lack of electrification experience. Was unknown signal cable routing the fault of NR? I would say it was the fault of BR or Railtrack.

Agreed entirely, the 2015 announcements (MML and North TPE) were just the "icing on the cake".
 
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