GWR Class 800

[MG11]

Forgive the confusion of a newbie, but what's the actual difference between 800 and 802? As I understand it they're both bi-mode versions of the same thing?

Forgive the confusion of a newbie, but what's the actual difference between 800 and 802? As I understand it they're both bi-mode versions of the same thing?

Forgive the confusion of a newbie, but what's the actual difference between 800 and 802? As I understand it they're both bi-mode versions of the same thing?

800s = 5 Coach 802s= 7 Coach

 

[Domh245]

800s = 5 Coach 802s= 7 Coach

????? There are no 7 coach trains, only 5 cars and 9 cars, of which there are subfleets of both (ie 800/0s and 802/0s are 5 car, 800/3s and 802/1s are 9 car) - the main difference between them is the way they were sourced - the 800s are on a contract where Hitachi have to provide a certain number of trains every day, whilst the 802s are more conventional in that there are a number of trains that have been purchased by a ROSCO and will be used by the operator. Other than that, Fuel Tanks, engine software and braking resistors are the main differences off the top of my head

 

[JN114]

Forgive the confusion of a newbie, but what's the actual difference between 800 and 802? As I understand it they're both bi-mode versions of the same thing?

802s have Larger radiators and Fuel tanks. Engine management software different as no requirement to follow strict DfT performance restrictions.

From a lay-person perspective you won’t notice the difference.

 

[gsnedders]

No more than any other totally new design of stock.

Most totally new designs of stock haven't been running around on UK rails for years prior to introduction, though.

 

[Harbornite]

The class 800s have plus & minus points compared with a HST

plus = faster on electric, better ambience inside overall, quiet on diesel, excellent leg room better views out due to lower seat backs

You can add retention tanks and lack of slam doors to the list of plus points. Shorter dwell times and no more brown mist for track workers.

 

[TractiveEffort]

On the 8:17 today from Chippenham nice sharp acceleration from the platform then equally sharp breaking before clearing the platform! Fault with on board safety system apparently, took 15 mins to fix. Just seen first 802 at temple meads. interesting paper stickers in window saying kasado works 48th shipment.

ATP - 25 year old technology put into a new train, HST’s suffer from ATP issues, 800’s have suffered some issues as well, not sure what the answer is, as there certainly doesn’t seem to be any development and improvement of ATP and its with us for a while longer.

 

[Railperf]

Video comparing HST v IET departing Chippenham on diesel: https://twitter.com/GWRHelp/status/935188418652524544

This video is a farce. GWR should be ashamed of themselves posting this. A HST can pull away from a station much faster than that, and most often they do. Start both off in full power and there isn't much in it. Class 800's do beat a HST to a quarter mile but then the HST starts to catch up and overtake it. The accelerative advantage off a Class 800 IET is only to around 45 /50mph in diesel mode. in electric mode however, the 800's pull away without exception.

 

[Phil G]

Well I'm beginning to think Japanese reliability is a myth, after yesterday's issues the 07:00 starts 27 late from Paddington then gets overtaken by the 07:30 and is now being reported 52 late, presumably all due to a fault of some kind. Thankfully allowing the 07:30 past at some point has not held up the HST I'm now squeezed on. There has been some sort of issue every week since introduction and it's never been on time at Chippenham. Roll on wires!

 

[jimm]

Most totally new designs of stock haven't been running around on UK rails for years prior to introduction, though.

But the HST prototype did run around for some years and the production trains still suffered plenty of teething troubles in their early days.

 

[D365]

But the HST prototype did run around for some years and the production trains still suffered plenty of teething troubles in their early days.

Shh, no no, you can't say that!

 

[swaldman]

the main difference between them is the way they were sourced - the 800s are on a contract where Hitachi have to provide a certain number of trains every day, whilst the 802s are more conventional in that there are a number of trains that have been purchased by a ROSCO and will be used by the operator. Other than that, Fuel Tanks, engine software and braking resistors are the main differences off the top of my head

802s have Larger radiators and Fuel tanks. Engine management software different as no requirement to follow strict DfT performance restrictions.

OK, so contratual arcana aside, the 802s have bigger fuel tanks and a higher power limit? That makes sense if they were conceived as running longer and faster on diesel. Why the difference in braking resistors? Are they only used in diesel mode? (perhaps the braking power goes back into the wires when electric?)

 

[D365]

Why the difference in braking resistors? Are they only used in diesel mode? (perhaps the braking power goes back into the wires when electric?)

You already answered that. Longer running under diesel

 

[Domh245]

OK, so contratual arcana aside, the 802s have bigger fuel tanks and a higher power limit? That makes sense if they were conceived as running longer and faster on diesel. Why the difference in braking resistors? Are they only used in diesel mode? (perhaps the braking power goes back into the wires when electric?)

I'm not too sure on the specifics with the engines, but they both have the same peak power output. However, the 802s can stay at that power for longer than the 800s. The fuel tanks are as you note down to the fact that they're expected to operate more miles away from the wiring than the 800s. I think the braking resistors are a similar rationale - the 800s were expected to spend most of their time under the wires so any braking energy is returned to the overhead lines, so whenever they weren't under the wires, the conventional friction brakes were adequate. The 802s, spending more time away from the wires, would get through brake disks and pads at a far greater rate if they didn't have some other means of slowing the train down.

 

[swaldman]

I'm not too sure on the specifics with the engines, but they both have the same peak power output. However, the 802s can stay at that power for longer than the 800s. The fuel tanks are as you note down to the fact that they're expected to operate more miles away from the wiring than the 800s. I think the braking resistors are a similar rationale - the 800s were expected to spend most of their time under the wires so any braking energy is returned to the overhead lines, so whenever they weren't under the wires, the conventional friction brakes were adequate. The 802s, spending more time away from the wires, would get through brake disks and pads at a far greater rate if they didn't have some other means of slowing the train down.

Makes sense - thanks all

 

[Clarence Yard]

802s have Larger radiators and Fuel tanks. Engine management software different as no requirement to follow strict DfT performance restrictions.

From a lay-person perspective you won’t notice the difference.

The 800 fleet now have the larger fuel tanks too. The engine management software is identical - it is how that software is set up is the difference. The 800 units are optimised to reduce engine wear.

 

[YorkshireBear]

Shh, no no, you can't say that!

You can't say it because its a myth. The HST came out of the box ready to go with no issues and is in every way the perfect train.

 

[D1009]

Most totally new designs of stock haven't been running around on UK rails for years prior to introduction, though.

Why should UK rails be so different from others in that respect?

 

[Darandio]

No more than any other totally new design of stock.

Yet many moons ago when i've spoken about teething troubles, the response was that this train is already tried and tested in the form of the Class 395. So many differing opinions about what is new and what isn't.

 

[gsnedders]

Why should UK rails be so different from others in that respect?

Depends on the nature of the teething troubles, to be fair. If it's interactions with infrastructure (see Class 700's biggest issues in the early days, for example), then you might not hit them until you're regularly running down the line you will be in service. If it's down to climatic conditions, Velim probably isn't representative (and even in the UK, Old Dalby probably isn't representative of the line through Dawlish, for example).

 

[JN114]

The 800 fleet now have the larger fuel tanks too. The engine management software is identical - it is how that software is set up is the difference. The 800 units are optimised to reduce engine wear.

That’s interesting; I wasn’t aware the Fuel Tanks had been upgraded on the 800s - when I was doing platform validation back in May the Hitachi guys on board were saying that the floor needed strengthening to support the additional weight; and that this wasn’t possible due to the monocoque construction of the Bodyshell. Genuinely impressed if they have managed it as that means even greater interoperability/flexibility between the types during disruption if required.

How about the radiators? Did they get upgraded on the 800s in the end?

 

[D1009]

Will it be possible for a class 800 and a class 802 to work in multiple?

 

[Wilts Wanderer]

Yes, nothing prevents 800 / 802 sets from multi-working.

 

[jon0844]

I chatted with someone who works at Bounds Green depot for Virgin who said that the 800s have some issues with the coupling and are going back for modifications? He said something was stretching, but I didn't catch exactly what he meant?

Has this been discussed here?

 

[Railperf]

Interesting that the DfT specification specified a 75 minute London to Bristol journey time inclusive of 5 stops in Electric mode but excluding dwell time, recovery time, performance allowances etc. The current timetable seems to average out at 85.5 or 86.5 minutes running time, plus 9.5 minutes dwell time and 9 minutes of additional time for engineering, pathing and performance allowances. That seems to suggest IET has to achieve a time saving of almost 2 minutes per section based on traction and braking. Greater time savings would come on the 125mph sections - Paddington to Reading, Reading to Didcot, Didcot to Swindon and Swindon to Chippenham, and slightly less on the lower speed sections Chippenham to Bath and Bath to Bristol.
So far IET's have demonstrated superior acceleration in electric mode between Paddington and Maidenhead seems to save a minute over HST's, but that still seems to put more onus on superior braking by machine, and drivers needing to brake harder than they would in HST's.

 

[Filton Bank]

Yes, nothing prevents 800 / 802 sets from multi-working.

Nothing technical anyway. Contractual issues are another matter.

 

[Filton Bank]

I chatted with someone who works at Bounds Green depot for Virgin who said that the 800s have some issues with the coupling and are going back for modifications? He said something was stretching, but I didn't catch exactly what he meant?

Has this been discussed here?

Yes there have been some coupling/uncoupling issues, hence why GWR services are not splitting in service just yet, and continuing as 10 cars with the rear 5 locked out.

 

[43096]

ATP - 25 year old technology put into a new train, HST’s suffer from ATP issues, 800’s have suffered some issues as well, not sure what the answer is, as there certainly doesn’t seem to be any development and improvement of ATP and its with us for a while longer.

Answer is ETCS.

 

[43096]

You can't say it because its a myth. The HST came out of the box ready to go with no issues and is in every way the perfect train.

Press launch of HST went as planned, didn't arrive 40+ late and didn’t give the passengers a shower from the aircon. Not aware that the entire HST fleet was grounded, either...

 

[Dai Corner]

Answer is ETCS.

Which presumably would allow the IETs to run at their design speed and make as big a difference to journey times as the HSTs did.

 

[CardiffKid]

Not aware that the entire HST fleet was grounded, either...

The 800 fleet was four strong on the launch week and was 'grounded' for a day.

It's embarrassing for all concerned but hardly a calamity.