Trivia: Some facts about rolling stock which you probably didn't know

[SolomonSouth]

1. The Class 375/8, 375/9 and 376 share the same bogies (Bombardier P3-25 in the power cars, Bombardier T3-25 in the trailer cars)
2. The 375/3, /6 and /7 use different bogies to the /8 and /9 sub classes.
3. In fact, all the 377s, 378s, 379s and 387s share the same bogies with 375/8, 375/9 and 376. Despite the 376 and 378 being 75mph not 100mph.
4. Class 375-378 can all couple
5. The 357's brakes are labelled as air (rheostatic/regen) whilst all other electrostars are just Air (regenerative). What does this mean?
6. The 350, 380 and 444 share the same bogies BUT the 450 strangely does not.
7. The retractioned 455s are more powerful than the ones that still retain their original motors - 4*322 vs 4*250. This would presumably make them accelerate better?
8. The 465/2 /9 do NOT use the same traction motors as the 466. The 465/9 uses Alsthom G352BY, whilst the 466 uses Alstom G352AY. And yet they sound the same.
9. 317 and 318 both use the same bogies - BREL BP20 and BREL BT13. Not sure in what order though
10. 315801-841 use different traction motors to 315842-861 - 315801-841 use 8x Brush TM61-53 whilst 315842-861 use 8x GEC G310AZ. Anyone able to comment on sound/acceleration differences (if there are any)?
11. 313 and 315 have Air (Westcode) braking AND rheostatic, and yet the very similar 317, 318, 319, 320, 321, 322, 455 and 456 do not. The 507 and 508 do though.
12. 378/1s weigh a whopping 40 tonnes more than 378/2s despite not having overhead. Reason?
13. 395 "Javelins" can only couple 2 units max.
14. The Pendolino, the 458 and the 334 share the same traction motors - Alstom Onix 800.
15. 465/0, 465/1 and 466 have the same bogies and they do not share these with the 465/2 and 465/9.
16. The 465/2 and 465/9 are said to have Air (regenerative) braking yet it has been disabled in the units for a long time.
17. 700, 707 and 717 use the same bogies,
18. Finally, (this one is especially mind-boggling), the 172 and the 195 are the ONLY DMUs currently in service to use "Mechanical" transmission. All others use "Hydraulic". Can someone explain the differences between the two? Do the 172 and 195 have manual gear levers in their cabs? Or is it somehting else altogether?

Hope you enjoyed reading, and if there any facts I've missed, please add them in the comments.

 

[43096]

1. Did you know 350s and 360s use different motors? According to the 2020-2021 rolling stock review:

• The 350 uses 4x Siemens 1TB2016-0GB02
• The 360 uses 4x 1TB2016-0GB02 three phase

Before I even start on the rest of it, those are the same!

 

[Domh245]

Before I even start on the rest of it, those are the same!

Similarly, point 15 the only difference is the capitalisation of ONIX, they're the same otherwise.

Other ones that have jumped out -
7. I'm fairly sure that all first generation Desiros are fitted with SF5000 bogies
12. 313/315 are not at all similar to the 317-322 & 455-456 - the former are PEP (with 2 motored vehicles), whilst the latter are Mk3 based (with single motor vehicle)
19. Mechanical transmission means that they their gearbox has actual metal gears to transmit power from the engine to the wheels. whilst hydraulic transmissions used oil-filled reservoirs & impellers. From the cab controls there is no difference, still just a power controller and a direction controller

 

[O L Leigh]

6. The 357's brakes are labelled as air (rheostatic/regen) whilst all other electrostars are just Air (regenerative). What does this mean?

The difference between rheostatic and regenerative braking is that on rheo brake the excess power generated by the motors during braking wasted through banks of resistors and lost to atmosphere as heat. With regen the power is returned to the grid through the pantograph/shoes, therefore it can only be used if there is an electrical connection (e.g. the train is not off the juice). I would wait for someone else to comment, but I am unsure whether Cl357s have the capability to do both as most Electrostars go straight back to air operated friction brakes if they lose electrical connection to the supply (e.g. OLE neutral section or CRE "gap").

10. 317 and 318 both use the same bogies - BREL BP20 and BREL BT13. Not sure in what order though

BP = Bogie Powered
BT = Bogie Trailer

11. 315801-841 use different traction motors to 315842-861 - 315801-841 use 8x Brush TM61-53 whilst 315842-861 use 8x GEC G310AZ. Anyone able to comment on sound/acceleration differences (if there are any)?

There are none.

12. 313 and 315 have Air (Westcode) braking AND rheostatic, and yet the very similar 317, 318, 319, 320, 321, 322, 455 and 456 do not. The 507 and 508 do though.

Cl315s do not have rheo brakes.

Have you been getting these "facts" off Wikipedia...?

 

[37057]

Pendos and 334s do not share the same motors either.

 

[pdeaves]

9. The 465/2 /9 do NOT use the same traction motors as the 466. The 465/9 uses Alsthom G352BY, whilst the 466 uses Alstom G352AY. And yet they sound the same.

For the Networker family, is the sound more to do with the controlling electronics than the actual motor?

 

[SolomonSouth]

Before I even start on the rest of it, those are the same!

But the 350’s aren’t “three-phase” like the 360s are

Cl315s do not have rheo brakes.

Have you been getting these "facts" off Wikipedia...?

No, mostly the rolling stock review 2020-2021 book. Buy it here: https://pocketmags.com/modern-railways-magazine/rolling-stock-review-2020-2021

There are none.

Weird, because they use different motors

 

[43096]

But the 350’s aren’t “three-phase” like the 360s are

That’s just you not understanding. Siemens do not make motors with the same model number that are both three phase and not. All the 350/360/450 series Desiros use three phase AC motors.

 

[SolomonSouth]

That’s just you not understanding. Siemens do not make motors with the same model number that are both three phase and not. All the 350/360/450 series Desiros use three phase AC motors.

Thx

 

[swt_passenger]

But the 350’s aren’t “three-phase” like the 360s are

Well, all this means then is that you just don’t understand that the whole point of modern AC traction systems is to make the use of 3 phase motors possible. The editor of the source document has randomly included “three phase” when it is completely redundant, because all AC rail traction motors are already 3 phase by definition.

 

[Domh245]

That’s just you not understanding. Siemens do not make motors with the same model number that are both three phase and not. All the 350/360/450 series Desiros use three phase AC motors.

I think it's also some pretty sloppy editing/proofing by whoever published the referenced book

Weird, because they use different motors

Motors of themselves are just spinning bits of metal inside a casing. They don't make much noise of themselves (it's transmissions and control electronics that tend to be the noisy bits), and when dual-sourced tend to be specified to have near identical torque/power so that they perform the same.

because all AC rail traction motors are already 3 phase by definition.

Not sure that's quite right? Most AC traction motors are 3 phase, but there's no reason that they have to be 3 phase - you could conceivably have a single phase AC traction motor if you wanted?

 

[swt_passenger]

I think it's also some pretty sloppy editing/proofing by whoever published the referenced book
[…]
Not sure that's quite right? Most AC traction motors are 3 phase, but there's no reason that they have to be 3 phase - you could conceivably have a single phase AC traction motor if you wanted?

In the current modern traction scene they are all 3 phase. But yes in theory you could use them scaled up in the way they appear in domestic appliances, ie “universal motors”. As you say this is more sloppy editing enabling incorrect inferences to be made.

 

[Peter C]

I think it's also some pretty sloppy editing/proofing by whoever published the referenced book

The book in question was edited by Colin J. Marsden, and published by Key Publishing.

-Peter

 

[43096]

The book in question was edited by Colin J. Marsden

That’s all we need to know. Read at your own risk and apply a heavy BS filter.

 

[supervc-10]

19. Mechanical transmission means that they their gearbox has actual metal gears to transmit power from the engine to the wheels. whilst hydraulic transmissions used oil-filled reservoirs & impellers. From the cab controls there is no difference, still just a power controller and a direction controller

It's kind of like the difference between a conventional automatic transmission in a car and a DSG transmission. From the driver's point of view, not much changes- you have a lever, put it in D, press the loud pedal. But a DSG has actual gears that mesh together and are moved around by selector forks (and a pair of clutches- which I'm not sure the 172s & 195s have), whereas a torque converter automatic has epicyclical gears which are sequentially locked in place for different ratios.

 

[swt_passenger]

That’s all we need to know. Read at your own risk and apply a heavy BS filter.

Never knowingly accepts proposed amendments, because he‘s never been wrong…

 

[O L Leigh]

Weird, because they use different motors

No it’s not. In fact it’s the very antithesis of weird.

These units were always intended to be worked together as a single fleet so it makes sense for them to have broadly similar performance. Also, how much difference in sound do you expect to get from similar motors rated for the same output.

 

[ac6000cw]

In the current modern traction scene they are all 3 phase. But yes in theory you could use them scaled up in the way they appear in domestic appliances, ie “universal motors”.

AFAIK, in countries with high-voltage, low-frequency AC electrification e.g. 15kV, 16 2/3 Hz as used in Germany/Austria/Switzerland, the use of series-wound single-phase AC motors ('universal motors') was normal until solid-state electronic power conversion and control became practical for rail traction purposes.

Being able to use such motors was actually the reason for the use of a low-frequency AC supply (AFAIK, 50/60 Hz 'universal motors' are not very suitable for rail traction use).

 

[Mikey C]

19. Mechanical transmission means that they their gearbox has actual metal gears to transmit power from the engine to the wheels. whilst hydraulic transmissions used oil-filled reservoirs & impellers. From the cab controls there is no difference, still just a power controller and a direction controller

Indeed the 172s sound different from the other Turbostars as a result, as you hear when the gear has been changed (as in a car or bus or any other vehicle with a conventional gearbox)

 

[D365]

Crikey. Time to break out the red correcting pen…

 

[hexagon789]

Never knowingly accepts proposed amendments, because he‘s never been wrong…

Making rather a mockery of the 'any corrections welcome' note carried within...

 

[mightyena]

4. Class 375-378 can all couple

I'm gonna call "it depends". I thought pretty much all electrostars (and dellner fitted turbostars) are mechanically compatible, but there are a lot of combinations that aren't allowed to actually operate like that outside of an emergency. 377/4 and 377/6 springs to mind. Whether that's a fundamental electrical incompatibility or just a lack of paperwork I'm not sure.

10. 315801-841 use different traction motors to 315842-861 - 315801-841 use 8x Brush TM61-53 whilst 315842-861 use 8x GEC G310AZ. Anyone able to comment on sound/acceleration differences (if there are any)?

Not any more. In fact, I believe the motors are so similar that they are interchangeable. Brush units have had faulty motors replaced with GEC ones and vice versa.

12. 378/1s weigh a whopping 40 tonnes more than 378/2s despite not having overhead. Reason?

40 tonnes sounds about right for the approximte mass of a cl378 MSO. Are you sure you're not comparing a 5 car 378/1 with a 4 car 378/2?

17. 700, 707 and 717 use the same bogies,

Not surprising, since they are basically all identical units built more or less simultaneously, with the 717s actually being an extension of the 700 order/

18. Finally, (this one is especially mind-boggling), the 172 and the 195 are the ONLY DMUs currently in service to use "Mechanical" transmission. All others use "Hydraulic". Can someone explain the differences between the two? Do the 172 and 195 have manual gear levers in their cabs? Or is it somehting else altogether?

Not that mind boggling.
Mechanical transmission = power from the engine is transferred to the wheels mechanically - through physical gears. The gearbox itself is automatic.
Hydraulic transmission = the power from the engine is transferred to the wheels hydraulically - using some sort of fluid.

 

[southern442]

Slightly off-topic but why is it that 172s and 195s are mechanical whereas all others are hydraulic? Is it just a better way to do it for new build DMUs?

 

[hexagon789]

Slightly off-topic but why is it that 172s and 195s are mechanical whereas all others are hydraulic? Is it just a better way to do it for new build DMUs?

More fuel efficient for one, and better acceleration (though for 172s only in the 0-60 range, as I recall the overall acceleration to 100 is no better than a TurboStar/Clubman at least according to Porterbrook's fleet brochure).

A comparison can be made with Translink's fleet - the original 2004 C3K units use hydraulic transmission but the newer C4K units have a ZF 6-speed transmission and apparently use about 7% less fuel, though they are about 4 tonnes lighter per car due to lack of auxiliary engine.

 

[dgl]

As I understand, though, the fuel savings going for a mechanical transmission over a hydraulic transmission depend on the stopping pattern and when SWT tried a mechanical transmission in one of their 159's there was at most marginal fuel savings as a hydraulic transmission as used in the 159 is more efficient at high speeds than the mechanical box, primarily, I believe, due to the mechanical transmission used being unable to coast.

 

[hexagon789]

As I understand, though, the fuel savings going for a mechanical transmission over a hydraulic transmission depend on the stopping pattern and when SWT tried a mechanical transmission in one of their 159's there was at most marginal fuel savings as a hydraulic transmission as used in the 159 is more efficient at high speeds than the mechanical box, primarily, I believe, due to the mechanical transmission used being unable to coast.

I think generally it's better for more short-hope suburban stuff where stations are closely spaced and acceleration is more important than maximum speed. For longer distance runs at higher speeds the ability of hydraulic transmission to allow prolonged coasting is more efficient. Of course, you do get mechanical transmissions with freewheel coasting ability; you could certainly coast freely on First Gen units

 

[Irascible]

As I understand, though, the fuel savings going for a mechanical transmission over a hydraulic transmission depend on the stopping pattern and when SWT tried a mechanical transmission in one of their 159's there was at most marginal fuel savings as a hydraulic transmission as used in the 159 is more efficient at high speeds than the mechanical box, primarily, I believe, due to the mechanical transmission used being unable to coast.

The Voith transmissions use a torque converter up to about 40ish mph, and then basically lock the engine & driveshaft ( through a fluid coupling, so it's not literally locked ) so it's pretty mechanically simple... seems wierd that the mechanical box couldn't coast though.

 

[hexagon789]

The Voith transmissions use a torque converter up to about 40ish mph, and then basically lock the engine & driveshaft ( through a fluid coupling, so it's not literally locked ) so it's pretty mechanically simple... seems wierd that the mechanical box couldn't coast though.

Varies, depending on maximum speed and actual power notch. A 75mph Sprinter might change 'up' at anything from 30 to 45mph.

As to the ZF, lack of freewheel might be a better term. You can 'coast' in the sense of running with no power applied but the train is permanently 'in gear', so you have the engine braking effect as with cars.

 

[Irascible]

Varies, depending on maximum speed and actual power notch. A 75mph Sprinter might change 'up' at anything from 30 to 45mph.

Vaguely around half speed was my understanding of intent, as you say depending on characteristics of what it's bolted to. Not sure I've had any experience of one accelerating in anything but highest notch in the wild! ( what's that, 3 in a sprinter? is there anything else running around these days with one? I've totally lost track ).

As the ZF, lack of freewheel might be a better term. You can 'coast' in the sense of running with no power applied but the train is permanently 'in gear', so you have the engine braking effect as with cars.

Yes, that was my takeaway, it just seems a strange and simple thing to leave out. Although, do you freewheel after the box & have the idling engine still turning the gears, before the box & have the wheels do it, freewheel both sides, or have a neutral position where everything is turning but not meshed. Anything seems better than nothing!