Class 810 (was originally class 804) for East Midlands Railway Construction/Introduction Updates

py_megapixel

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Issues with windows and seat alignments are one thing, but that seems to plague other builds regardless of door type and manufacturers.
Very true. The 390s are famous for having seats where you're staring at a blank piece of plastic, and they have plug doors.

I can't personally think of any converse examples, where a train with pocket doors has a notably praised seat layout, but they must surely exist somewhere.

There is also an operational issue when plug doors fail to close. The train will usually be out of gauge, either calling for mechanic intervention on running lines, or clearance to run in that state to an off-route stowage, (I'm sure there's a 'railway term' for that type of movement).
The out of gauge issue is much more important on a system with limited clearances like the UK's.
Isn't running the train with the doors open considered completely unacceptable?

I know it's permitted to override the interlock circuit in exceptional conditions, but I thought that staff still had to be certain that all doors were closed before starting.
 
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hexagon789

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Sorry to stray off-topic a bit, but as mentioned, pocket sliding doors are used across most of the rail manufacturers in Japan, and probably why Hitachi is sticking to something it's more familiar with door-wise for their products. Very few rollingstock in Japan are ever built with plug sliding doors. Most of the shinkansen models are built with pocket doors, compared to European units which prefer outward sliding plug doors in some cases. One model series, the E3 built by Kawasaki and Tokyu (now J-Trec), are fitted with plug doors that are flush to the body, though they still act like pockets doors as they slide inward.

I feel that in the UK and Europe, manufacturers might prefer outward sliding plug doors to pocket doors when it comes to situations about using wall space since it can change the available space within a train. But since Hitachi is using them, it doesn't seem like an issue on that front. Issues with windows and seat alignments are one thing, but that seems to plague other builds regardless of door type and manufacturers.
I suppose I can understand Hitachi making the decision they did if plug doors are uncommon on Japanese trains, just the thing about reliability doesn't ring true.

Isn't running the train with the doors open considered completely unacceptable?
With passengers I would think so, empty at caution to clear the line I'm sure has happened even recently.
 

py_megapixel

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I suppose I can understand Hitachi making the decision they did if plug doors are uncommon on Japanese trains, just the thing about reliability doesn't ring true.
But if Hitachi are used to building for the Japanese market, then to them, plug doors are a rather experimental technology, so their reliability is not necessarily proven to be poor, but rather unproven.

And given that they have been contracted to build several hundred carriages to modernise the inter-city rail network of pretty much an entire country, they probably don't want to be using experimental technology for it.
 

AM9

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Very true. The 390s are famous for having seats where you're staring at a blank piece of plastic, and they have plug doors.

I can't personally think of any converse examples, where a train with pocket doors has a notably praised seat layout, but they must surely exist somewhere.


Isn't running the train with the doors open considered completely unacceptable?

I know it's permitted to override the interlock circuit in exceptional conditions, but I thought that staff still had to be certain that all doors were closed before starting.
I wasn't intimating that a train runs coaches with open doors and passengers. I expect the drill is to evacuate the coach and lock it off until the train reaches a station where the passengers can be off-loaded. That would be the same for any door type, plug or sliding. The issue with plug doors is that when not fully closed, there can be intrusions onto the safe zone of the structure gauge or that for adjacent tracks. In that case, before the train was moved, it might involve a mechanic to close and secure the door, or even remove it before the train can be moved. Alternatively, it might need the adjacent tracks to be cleared to allow the train to move.
 

DavidB

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But if Hitachi are used to building for the Japanese market, then to them, plug doors are a rather experimental technology, so their reliability is not necessarily proven to be poor, but rather unproven.

And given that they have been contracted to build several hundred carriages to modernise the inter-city rail network of pretty much an entire country, they probably don't want to be using experimental technology for it.

They've managed it on the 385s without any issues! Really can't see how plug doors could be considered 'experimental' for any train manufacturer - they are technology which has been around for decades and a company like Hitachi would be more than capable of producing them.

Isn't the 80x based on a Japansese model of train? It would seem more likely that it was just easier for Hitachi to use an existing design.
 

PacificRail

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I suppose I can understand Hitachi making the decision they did if plug doors are uncommon on Japanese trains, just the thing about reliability doesn't ring true.

It depends really. Based on what's been described, the doors are similar to or close to the ones used for both Shinkansen and express sets in Japan. Though when it comes to pocket doors even in Japan they have their own issues such as rattling, but it varies greatly on the mechanism and the train type. Plug doors have their issues as well, though in different situations.

They've managed it on the 385s without any issues! Really can't see how plug doors could be considered 'experimental' for any train manufacturer - they are technology which has been around for decades and a company like Hitachi would be more than capable of producing them.

Isn't the 80x based on a Japansese model of train? It would seem more likely that it was just easier for Hitachi to use an existing design.

The class 385's are a special case, though I wondered if the doors on that class were sub-contracted out rather than Hitachi designed. They may have assembled it, but it might be another's product. There are times when a manufacture knows its limits and relies on a product from another to fill requirements.

Also the units are based on the A-Train product family in Japan. It is still highly customized for the UK market, as it only carries over similar construction methods than just bringing over an entire product.
 
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LowLevel

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It is very rare for plug doors to be unable to close. They usually have ways of forcing them as a contingency.

If a train does have a door that can't close then it can move if need be, with passengers moved from the vehicle and out of service as soon as practical or empty stock, if a guard is provided they are required to travel in the affected vehicle to monitor it.
 

Bletchleyite

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There is also an operational issue when plug doors fail to close. The train will usually be out of gauge, either calling for mechanic intervention on running lines, or clearance to run in that state to an off-route stowage, (I'm sure there's a 'railway term' for that type of movement).
The out of gauge issue is much more important on a system with limited clearances like the UK's.

I've not ever seen a plug door failure where it was impossible to close the door even manually. Has anyone?

The class 385's are a special case, though I wondered if the doors on that class were sub-contracted out rather than Hitachi designed.

They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over, Kiekert is a common manufacturer in Germany and Wellman Peters made the Pacer bus doors. Goodness knows why I remember stuff like that! :)
 

LowLevel

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I've not ever seen a plug door failure where it was impossible to close the door even manually. Has anyone?



They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over, Kiekert is a common manufacturer in Germany and Wellman Peters made the Pacer bus doors. Goodness knows why I remember stuff like that! :)

Yes, seized door swing arm bearings on a 158 requiring the door to be removed.
 

Domh245

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They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over,

Could be IFE, now part of Knorr-Bremse?
 

Pacerman99

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I've not ever seen a plug door failure where it was impossible to close the door even manually. Has anyone?



They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over, Kiekert is a common manufacturer in Germany and Wellman Peters made the Pacer bus doors. Goodness knows why I remember stuff like that! :)
I saw a Mk 4 door get stuck at Stevenage back in GNER days.
 

DavidB

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They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over, Kiekert is a common manufacturer in Germany and Wellman Peters made the Pacer bus doors. Goodness knows why I remember stuff like that! :)

The mechanism and the door leaves may not be from the same supplier either - seem to recall that the Chiltern Mk3s have the same door mechanism as the Class 444 but a custom-designed door leaf (as they had to - it needs to match the profile of the bodyshell).
 

Railperf

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The previous graphs don't show that scenario to be fair - they just considered the notional acceleration assuming a maximum power of 1.25x continuous. The 125mph balancing comes from this graph which shows the maximum achievable acceleration for a given power (with total weight as published, and some assumed figures for rolling resistances and drag) with the IEP TTS acceleration profile thrown in for comparison. The 2MW profile hits zero just before 200kph so it'd never quite hit it, but 2MW is the "lower bound" if you like - we know that they've got more power than that available.

View attachment 91430

To actually reach 125mph (away from a lovely theoretical world with no headwind, perfectly straight and level track, no passengers, etc) they'll clearly need more than the notional 2MW continuous (assuming my guesstimated values hold) - but the estimate of 2.6MW from @hwl would seem to be ample



The possible explanation here is that the other 80x, all being either part of or derived from, IEP with it's financially incentivised reliability will have had more power than strictly necessary thrown at them so that they can still keep to time (or be run even faster, etc) with motors out.

810 being later, and a different design without the same procurement, they can take a more aggressive approach having gained experience on the reliability of their equipment (and not worrying about being stung as hard if motors drop out)
It doesn't make sense for Hitachi to be using GU's that generate 2940 kW for only 2000kW of traction motors. If 85% of the diesel power is available for traction, then there is still 2500kW available to power the motors if the traction system demands full power. And assuming @Domh245 figures are correct, this train also needs to meet a 10% overspeed on the flat - so 137.5mph. That won't be possible if 2000kW barely gets you to 125mph. The 125mph sections on the MML are quite short, so you need a train with enough 'shove in the back' to get you from 100-125mph or 110 to 125mph in a reasonably quick time. Fortunately those 125mph sections are positioned strategically on flat or downhill grades - but will 2000 kW maintain 110mph going up Sharnbrook? and the other MML gradients?

The original HST specification called for the 4500 hp combined engine power output to maintain a minimum 110mph up some of the long 1 in 200 gradients on the ECML. On the GWML, the longest continuous gradients on the high speed sections were around 1 in 300 , requiring around 3800 hp .

I'm not sure how the rolling resistance of a 10-car Class 810 will compare with a 2+8 HST, but clearly the HST seems to have better a cleaner aerodynamic shape, even if the nose on the front isn't quite as pointy.

If our experience with the 800/802 series units is anything to go by, the power available to the traction system will likely be set up to deliver maximum power from a standing start - ramping back up to high speed. But that still suggests more than 2000 kW will be needed. Exactly how much can be determined by someone who understands physics better than me. I would guess that the continuous power rating needs to be around 2200kW - the one hour rating just needs to be greater than 2500kW?
 

37057

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They normally are bought in anyway, you tend to see little plaques on the door top indicating which company. I recall that Desiro doors are made by a company called IFR, though I can't find their website so they may have been taken over, Kiekert is a common manufacturer in Germany and Wellman Peters made the Pacer bus doors. Goodness knows why I remember stuff like that! :)

Desiro (classic) doors - Bode.
 

Domh245

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If our experience with the 800/802 series units is anything to go by, the power available to the traction system will likely be set up to deliver maximum power from a standing start - ramping back up to high speed. But that still suggests more than 2000 kW will be needed. Exactly how much can be determined by someone who understands physics better than me. I would guess that the continuous power rating needs to be around 2200kW - the one hour rating just needs to be greater than 2500kW?

Full torque maybe, but full power won't be achieved straight away (Remember that power is force*velocity or in rotation terms torque*angular velocity - to achieve full power at low speeds would require silly high amounts of torque. Indeed, graph I posted in #840 shows power ramping up fairly linearly to around 50kph before then flattening off and gradually increasing again at higher speeds (which corresponds to a flat torque to start which then drops away)

The relation between peak and continuous power is pretty nebulous as it's mostly down to thermal management of the entire system (motors and controllers) as far as I can tell, and indeed the way in which the continuous rating for these motors has been defined is not entirely clear either - is it a 1 hour rating, or a theoretical infinite power output in a room at 20°, etc? The complexity of modern VVF motors and inverters also makes calculating things a lot more complicated than DC motors!

Determining the necessary peak power is also a bit of a dark art, as it's dependant on the train parameters, loading, weather, and just how quickly you actually want to go! Doing an estimated worst case to get these to a balancing speed of 137.5mph up a 1:100 gradient with an extra 30t in passengers (~400 passengers) in a 30mph headwind with the rolling resistance parameters the same as I've used throughout, I get to a required power output of 5.4MW, which seems excessive, and a highly improbable situation. Taking Sharnbrook as a more reasonable worst case (1:120 at 110mph) you only need 3.4MW for the same 30t load and strong headwind, but with aerodynamic drag being the predominant factor at high speeds (dropping the headwind to zero in the Sharnbrook scenario drops power to 2.5MW) without knowing the actual drag coefficient and area it's all just guesswork and fancy graphs!

I will say it again though, the odds of Hitachi dropping the ball and making a 125mph unit that's incapable of reaching 125mph seems slim, so they've clearly got confidence in the ability of the motors to get these up to 125mph and beyond - the big worry ia that with only 8 motors and 2 traction converters, at anything less than 100% reliability they're gonna be pretty poor, particularly in leaf-fall!
 

hexagon789

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But if Hitachi are used to building for the Japanese market, then to them, plug doors are a rather experimental technology, so their reliability is not necessarily proven to be poor, but rather unproven.

And given that they have been contracted to build several hundred carriages to modernise the inter-city rail network of pretty much an entire country, they probably don't want to be using experimental technology for it.
And it's probably easier for them as well.

I will say it again though, the odds of Hitachi dropping the ball and making a 125mph unit that's incapable of reaching 125mph seems slim, so they've clearly got confidence in the ability of the motors to get these up to 125mph and beyond - the big worry ia that with only 8 motors and 2 traction converters, at anything less than 100% reliability they're gonna be pretty poor, particularly in leaf-fall!
I'm sure they will be capable of 125, I think it's a case of trying to compare something which doesn't exist in the flesh yet with something which does but difers from it.

Not sure the 8 motors will be problematic in poor adhesion conditions, modern WSP systems are very good at managing power output at the wheels to get the best acceleration while minimising excessive slip
 

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Not sure the 8 motors will be problematic in poor adhesion conditions, modern WSP systems are very good at managing power output at the wheels to get the best acceleration while minimising excessive slip

My concern is more about poor adhesion (and performance more generally for that matter) with one of the traction packs out - they'll eventually get going, but not very quickly!
 

hexagon789

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My concern is more about poor adhesion (and performance more generally for that matter) with one of the traction packs out - they'll eventually get going, but not very quickly!
I see your point, though wouldn't they be arranged so that most failures would perhaps only affect one traction motor - a faulty motor wouldn't affect the rest of the ones on that car I mean, so that only in exceptional circumstances would the train be running on just one motor car of 4 motors.
 

Domh245

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I see your point, though wouldn't they be arranged so that most failures would perhaps only affect one traction motor - a faulty motor wouldn't affect the rest of the ones on that car I mean, so that only in exceptional circumstances would the train be running on just one motor car of 4 motors.

For sure - a single traction motor out (whilst not ideal) isn't the end of the world - but it's the second scenario that's the problematic one! I don't know enough to say how any failure would affect the systems, but I'd think that the whole pack dropping out is more likely than a single motor (though admittedly both are unlikely) - a motor of itself is pretty 'dumb' and so relatively unlikely to go wrong, but the traction packs are more complicated and thus seem more likely to fail (and critically, be a single point of failure), though I'd think there'll be some degree of redundancy in them.
 

hexagon789

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For sure - a single traction motor out (whilst not ideal) isn't the end of the world - but it's the second scenario that's the problematic one! I don't know enough to say how any failure would affect the systems, but I'd think that the whole pack dropping out is more likely than a single motor (though admittedly both are unlikely) - a motor of itself is pretty 'dumb' and so relatively unlikely to go wrong, but the traction packs are more complicated and thus seem more likely to fail (and critically, be a single point of failure), though I'd think there'll be some degree of redundancy in them.
What precisely are the traction packs, are they motors collectively in conjunction with all the various items required to power them? Just trying to understand how they form a single point of failure
 

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What precisely are the traction packs, are they motors collectively in conjunction with all the various items required to power them? Just trying to understand how they form a single point of failure

It's (almost - they actually call them traction packages, at least in an operations POV) what Hitachi call the inverters/"Drive converters" - each one feeds 4 TMs - if it drops out you loose all motors that it feeds (and the engines that feed it as well)

Image taken from the IEP development paper

1614542425572.png
 

hexagon789

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It's (almost - they actually call them traction packages, at least in an operations POV) what Hitachi call the inverters/"Drive converters" - each one feeds 4 TMs - if it drops out you loose all motors that it feeds (and the engines that feed it as well)

Image taken from the IEP development paper

View attachment 91613
Ah right, got you. The use of "traction package" rather confused me as I wasn't sure what it was intended to refer to and it seemed a rather 'catch-all' sort of term. I can see what you mean about a single point of failure, but I suppose it's better than a train with only one motor car; can't have everything.
 

Railperf

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But a 10-car 810 has 5880kW of diesel engines, and 4000kW of traction motors, so that should easily be enough, won't it?
Having a rethink here. A 2+8 HST had 3540 rail horse power vs a potential 5364hp for 2 x 5-car Class 810's. So why are we doubting the ability of a Class 810 to do 125mph?

Weight is similar for the two consists, but an IET roof has all the aerodynamics of a ploughed field but almost 1800 hp more than the HST. That's a fair amount of extra power! So they should do 125mph easily - surely.
 

AM9

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Having a rethink here. A 2+8 HST had 3540 rail horse power vs a potential 5364hp for 2 x 5-car Class 810's. So why are we doubting the ability of a Class 810 to do 125mph?

Weight is similar for the two consists, but an IET roof has all the aerodynamics of a ploughed field but almost 1800 hp more than the HST. That's a fair amount of extra power! So they should do 125mph easily - surely.
I suppose it's inevitable that failures in service will occur and possibly more often in their early days. If the 810s are in traction equipment terms virtually the same as the 800/802s, the early failures should be limited more to manufacturing infant mortalities, which means not only less disruption than the earlier 8xxs but more knowledge and provisioning for dealing with them when they do fail.
The railway has lived with HST reliability for over 40 years, and trains do sometimes need to continue on their journey with half the power and crucially, half the adhesion. The latter issue could have been addressed with a bussed generator line (à la class 769), but that is a whole new ball game.
 
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supervc-10

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Regarding doors- I was on a SEPTA train heading north from Philadelphia about a decade ago and the door was wide open. Sliding pocket type I think.
I went to find the bathroom and walked through to the next car to find it. Went to tell the guard- she seemed completely nonplussed by it being wide open. Which I found particularly odd in the litigation happy USA!!
 

hwl

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Really can't see how plug doors could be considered 'experimental' for any train manufacturer - they are technology which has been around for decades and a company like Hitachi would be more than capable of producing them.
All the European manufacturers buy in the plug doors from just 2 (/3?) firms, they don't actually produce them. Hence Hitachi sticking to doing something it does in house in Japan rather than outsourcing. The European manufacturers had lots of issues to begin with when starting to buy in plug doors.

Ah right, got you. The use of "traction package" rather confused me as I wasn't sure what it was intended to refer to and it seemed a rather 'catch-all' sort of term. I can see what you mean about a single point of failure, but I suppose it's better than a train with only one motor car; can't have everything.
The big (usually grey) box box underneath which contains all the electronics. Modern units combine as much as possible into single box adding the auxiliary supplies and more TMs than the older generation of stock. (e.g. 6 TMs and Auxiliary supply in some of the 345s boxes). Each traction motor is still fed from it own independent 3 phase variable speed drive, there just happen to be 4/6 drives for TMs and 2 similar converters for Auxiliary supply in a box rather than 3/4 boxes as on Electrostar (e.g. 2 drives per box).
The internal design is done to prevent as many SPoF issues as possible. The reality is very different to that schematic. For example combining everything into 1 box means having several independent cooling fans systems is much easier (and lighter)
The 810s are no different to the 800-802 and Aventra / Desiro City in terms of traction pack integration.

Having a rethink here. A 2+8 HST had 3540 rail horse power vs a potential 5364hp for 2 x 5-car Class 810's. So why are we doubting the ability of a Class 810 to do 125mph?

Weight is similar for the two consists, but an IET roof has all the aerodynamics of a ploughed field but almost 1800 hp more than the HST. That's a fair amount of extra power! So they should do 125mph easily - surely.
Exactly 5364hp continuous or something like 6700hp max for 2x5 car which should be fine and twice the number of powered wheels.

Full torque maybe, but full power won't be achieved straight away (Remember that power is force*velocity or in rotation terms torque*angular velocity - to achieve full power at low speeds would require silly high amounts of torque. Indeed, graph I posted in #840 shows power ramping up fairly linearly to around 50kph before then flattening off and gradually increasing again at higher speeds (which corresponds to a flat torque to start which then drops away)

The relation between peak and continuous power is pretty nebulous as it's mostly down to thermal management of the entire system (motors and controllers) as far as I can tell, and indeed the way in which the continuous rating for these motors has been defined is not entirely clear either - is it a 1 hour rating, or a theoretical infinite power output in a room at 20°, etc? The complexity of modern VVF motors and inverters also makes calculating things a lot more complicated than DC motors!

Determining the necessary peak power is also a bit of a dark art, as it's dependant on the train parameters, loading, weather, and just how quickly you actually want to go! Doing an estimated worst case to get these to a balancing speed of 137.5mph up a 1:100 gradient with an extra 30t in passengers (~400 passengers) in a 30mph headwind with the rolling resistance parameters the same as I've used throughout, I get to a required power output of 5.4MW, which seems excessive, and a highly improbable situation. Taking Sharnbrook as a more reasonable worst case (1:120 at 110mph) you only need 3.4MW for the same 30t load and strong headwind, but with aerodynamic drag being the predominant factor at high speeds (dropping the headwind to zero in the Sharnbrook scenario drops power to 2.5MW) without knowing the actual drag coefficient and area it's all just guesswork and fancy graphs!

I will say it again though, the odds of Hitachi dropping the ball and making a 125mph unit that's incapable of reaching 125mph seems slim, so they've clearly got confidence in the ability of the motors to get these up to 125mph and beyond - the big worry ia that with only 8 motors and 2 traction converters, at anything less than 100% reliability they're gonna be pretty poor, particularly in leaf-fall!
8 Motors and 8 traction inverters, just 2 sets of 4 inverters in a box together.
Having the motors on 2nd /4th cars means that the leading car's wheels help clean the rail head first unlike powercars / locomotives.
Continuous is effectively the latter, it also correlates to a stable long term motor operating temperature. Max is usually 1hour rating.
 
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hexagon789

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The big (usually grey) box box underneath which contains all the electronics. Modern units combine as much as possible into single box adding the auxiliary supplies and more TMs than the older generation of stock. (e.g. 6 TMs and Auxiliary supply in some of the 345s boxes). Each traction motor is still fed from it own independent 3 phase variable speed drive, there just happen to be 4/6 drives for TMs and 2 similar converters for Auxiliary supply in a box rather than 3/4 boxes as on Electrostar (e.g. 2 drives per box).
The internal design is done to prevent as many SPoF issues as possible. The reality is very different to that schematic. For example combining everything into 1 box means having several independent cooling fans systems is much easier (and lighter)
The 810s are no different to the 800-802 and Aventra / Desiro City in terms of traction pack integration.
Is the cooling ever a problem?

Having a rethink here. A 2+8 HST had 3540 rail horse power vs a potential 5364hp for 2 x 5-car Class 810's. So why are we doubting the ability of a Class 810 to do 125mph?

Weight is similar for the two consists, but an IET roof has all the aerodynamics of a ploughed field but almost 1800 hp more than the HST. That's a fair amount of extra power! So they should do 125mph easily - surely.
That's a good point, simply based on that comparison they should be capable of well over 125mph really
 

Railperf

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That's a good point, simply based on that comparison they should be capable of well over 125mph really
The 802's reach 119mph with appx 8.5hp/t - so an 810 with close to 11hp/t should do more than that.
What is interesting here is how HST's and Class 802's with similar power to weight ratios differ in performance. The 802's start off the line much faster in diesel mode, but peter out more quickly - reaching around 119mph on level track - whereas HST's still motor on to 125mph and beyond. Back in the early days - HST speeds around 133 to 136mph were commonly recorded before speed limiters were fitted.
I wonder whether the Class 800/802's seemingly inferior 'ploughed field' roof aerodynamics are a factor here?
 
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