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Triple system electric rolling stock?

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Peter301184

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Kinematic gauging may be simple in the theoretical explanation, but gauge clearing excercises are a lot of work that is often complex.

I didn't mean it to sound simple in practice, just that the basic theory of it is simple to understand.
 

LE Greys

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A locomotive would probably need 2 pans up for 750V overhead see http://www.flickr.com/photos/peters452002/4411505281/ which runs on 850V

The 70s and 71s only had a single pantograph, but then they were not going particularly fast when they were using it.

I travelled the whole length of that line a couple of years ago. Fascinating. Never knew it was a different voltage as well as being metre-gauge.
 

starrymarkb

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The 70s and 71s only had a single pantograph, but then they were not going particularly fast when they were using it.

I travelled the whole length of that line a couple of years ago. Fascinating. Never knew it was a different voltage as well as being metre-gauge.

Most of the Swiss Private lines are weird and wonderful voltages.

Eg: Interlaken Ost has 15kV Standard Gauge (BLS), 15kV Metre Gauge (ZentralBahn) & 1500V DC (BOB) - The nearby WAB and SPB are 1500V 800mm Gauge, then further up the mountain the JungfrauBahn uses a weird three phase dual contact wire 1125V system (and is 1000mm gauge)

Similarly the RhB/MGB network is 11kV (though there were 1500V DV patches)!
 
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Back to the original question and in the context of Mersey, though it would probably be possible to create a triple voltage unit, for the 750 V dc OHL section, given that it's so short, it might be better to use a hybrid (electric with batteries / super capacitors) or bi-mode (electric with diesel) unit.

One issue for Mersey is the constrained height through the tunnels, which necessitates a low roofed unit, as per 507/508. Another is the extra weight that the dual / triple voltage kit would introduce and whether this would be worthwhile for the units that would spend all their lives on the 750 V dc third rail network.
 

Pumbaa

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One issue for Mersey is the constrained height through the tunnels, which necessitates a low roofed unit, as per 507/508.

Does it though? 66s are cleared through it, they must be higher than PEPs.
--- old post above --- --- new post below ---
Yes - 66s are 3.91m as opposed to PEP 3.58m. So could be higher.
--- old post above --- --- new post below ---
And to give an idea, the Electrostar family are 3.78m so they'd probably fit down too.
 

Hydro

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73's used to work down there on sandite trains, the 950 regularly goes down there and we've had 31's down there also.
 

Holly

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Does it though? 66s are cleared through it, they must be higher than PEPs.
Yes - 66s are 3.91m as opposed to PEP 3.58m. So could be higher.
And to give an idea, the Electrostar family are 3.78m so they'd probably fit down too.
You are referring to the Mersey tunnel though?

ISTR the clearances are huge in the Haymarket tunnel (not sure about the disused Woodside tunnel).
 

First class

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Merseyrail "loop-link" tunnels were apparantly designed to accomodate overhead electrification.

The "height" restrictions are myths. The only restriction is gangway doors and egress through cabs on to track in an emergency.
 

Holly

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Merseyrail "loop-link" tunnels were apparantly designed to accommodate overhead electrification.
The "height" restrictions are myths. ...
So it's conceivable then you could have 750vDC Overhead (in the style of Manchester Metrolink) all the way from Wrexham to Lime Street low level. And out into Wirral Waters, if it is ever built.

But as for the one mile from Rock Ferry to 12 Quays through the Haymarket tunnel, a diesel shunter is obvious solution.
 

First class

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So it's conceivable then you could have 750vDC Overhead (in the style of Manchester Metrolink) all the way from Wrexham to Lime Street low level. And out into Wirral Waters, if it is ever built.

But as for the one mile from Rock Ferry to 12 Quays through the Haymarket tunnel, a diesel shunter is obvious solution.

It would be easier and probably cheaper to just use normal AC electrication and time it all so Wrexham is wired by around 2017, just as new, (dual voltage), stock is appearing.

If I remember correctly, Merseyrail is due for major renewal in around 2020, i.e. complete resignalling, new crossovers, infrastructure etc etc.

I'd say 2015-2025 will be a very big period of change.
 

ChrisCooper

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The reason for the 507's low height is just because they share the same body shell as the 313s. Now, if the 313s are low height because of clearances in the tunnels to Moorgate is a good question, I've seen plenty saying yes, others catagorically denying it. Remember though loading gauge isn't just overall height but also profile. Actually a flatish roof like on the 313/507 makes less efficient use of the tube tunnel loading gauge as the roof is rounded. Just because a higher 66 can fit in a tunnel though doesn't mean anything can, as 66s have quite a sharp roof profile with the centre much higher than the sides.

To go back to the issue of tri-voltage trains and size, the size of Eurostars (or 92s) has nothing at all to do with being tri-voltage (or quad voltage as those that can run to the South of France on their 1500v system are), it's to do with the specific requirements for the channel tunnel. This includes the power (due to the length of the train, remember a single Eurostar powercar is hauling about the same as 2 TGV powercars), and the redundancy (duplicated equipment, plus more power so that they can still move in the event of failure of some traction equipment, including climbing the steep grades in the tunnel). Adding on more voltages really isn't that hard, especially with the way modern traction systems work (they convert AC to DC then back to AC anyway). A 25kV train will be supplying low voltage DC to it's traction equipment anyway, so having a direct input of low voltage DC isn't a big deal. Different AC voltages just mean tapping onto the transformer at different points.
 

Peter301184

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To go back to the issue of tri-voltage trains and size, the size of Eurostars (or 92s) has nothing at all to do with being tri-voltage (or quad voltage as those that can run to the South of France on their 1500v system are), it's to do with the specific requirements for the channel tunnel. This includes the power (due to the length of the train, remember a single Eurostar powercar is hauling about the same as 2 TGV powercars), and the redundancy (duplicated equipment, plus more power so that they can still move in the event of failure of some traction equipment, including climbing the steep grades in the tunnel). Adding on more voltages really isn't that hard, especially with the way modern traction systems work (they convert AC to DC then back to AC anyway). A 25kV train will be supplying low voltage DC to it's traction equipment anyway, so having a direct input of low voltage DC isn't a big deal. Different AC voltages just mean tapping onto the transformer at different points.

Just a few points here.

Most TGV's are 200m long same as the Eurostar.
The Eurostar is a petite TGV restricted in size due to the tunnel and the Brittish gauge.
You say 'due to the length of the train, remember a single Eurostar powercar is hauling about the same as 2 TGV powercars' this is not true. The Eurostar has two power cars like all other TGV's.
Redundancy is used on all types of trains, not limited to just Eurostars. Redundancy equipment isn't really space consuming.
The line voltage into the BM's is 1500V DC, I wouldn't call that low voltage.
The smoothing equipment (common block) and power distribution is massive, bigger then the main transformer and so are the BM's. The power cars couldn't physically be any smaller using the current equipment used.
 

starrymarkb

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Just a few points here.

Most TGV's are 200m long same as the Eurostar.
The Eurostar is a petite TGV restricted in size due to the tunnel and the Brittish gauge.
You say 'due to the length of the train, remember a single Eurostar powercar is hauling about the same as 2 TGV powercars' this is not true. The Eurostar has two power cars like all other TGV's.
Redundancy is used on all types of trains, not limited to just Eurostars. Redundancy equipment isn't really space consuming.
The line voltage into the BM's is 1500V DC, I wouldn't call that low voltage.
The smoothing equipment (common block) and power distribution is massive, bigger then the main transformer and so are the BM's. The power cars couldn't physically be any smaller using the current equipment used.

I think they were meaning that a Eurostar is 400m (same as a double TGV), technically I guess it's one and a half powercars if you count the motor coaches
 

ChrisCooper

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A Eurostar half set is about the same length as a TGV but has a single powercar, wheras a TGV has two powercars. A full Eurostar set has 2 powercars, but it's about twice as long as a TGV. Two TGVs together have 4 powercars. A single Eurostar powercar has to be able to power a full Eurostar set out of the tunnel on it's own, up very steep gradients, a TGV does not.
 

Barrett M95

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Eurostar is twice the length of any other train in the TGV family as stated (400m vs 200m) and has more power packed into each end but has to make do with a smaller loading gauge.

Its nickname of "le petit TGV" is a slight misnomer as only from a straight ahead view does the 373 look smaller than an Atlantique, Thalys, PSE, duplex set etc... Just about every other stat makes it look much larger, mainly of course power and length.

As I'm sure many people here know, the restrictive loading gauge was due to running on Southern region networks which is now not strictly required.
 

Peter301184

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A Eurostar half set is about the same length as a TGV but has a single powercar, wheras a TGV has two powercars. A full Eurostar set has 2 powercars, but it's about twice as long as a TGV. Two TGVs together have 4 powercars. A single Eurostar powercar has to be able to power a full Eurostar set out of the tunnel on it's own, up very steep gradients, a TGV does not.

But the Eurostar has more power then most other tgv's. I really don't get what your debate is. I pointed out some factual points and your comparing tgv to eurostars.

The fact is for comparison that Eurostar have never run in service as a half set. The secability at the R9's is for emergency use only.

A Eurostar full set has power rating of 12,240KW, same as a NoL set.

Other TGV full sets have 'only' 8,800KW (apart from the TGV POS).

The power to weight shows that Eurostar 3 caps is still the most under powered train of all the TGV sets.

Sorry this topic has now diverted lol.
 

ChrisCooper

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But the Eurostar has more power then most other tgv's. I really don't get what your debate is. I pointed out some factual points and your comparing tgv to eurostars.

The fact is for comparison that Eurostar have never run in service as a half set. The secability at the R9's is for emergency use only.

Someone mentioned the "size" of Eurostars and implied this was due to their tri or quad voltage requirements. I was pointing out that the size of Eurostars (presumably they were refering to the length of the powercars and the fact that the outer end of the 1st trailer is also powered), is far more down to the high power output requirements of a Eurostar powercar than the need to work of multiple voltages. I gave an explanation for one of the reasons for the high output as being the length of the train, which is rougly twice as long as a TGV. I only brought up half sets to say that a single Eurostar halfset is about the length of a TGV but has one powercar. I didn't ever suggest they ran alone, which is irelevant to the point.
 

Peter301184

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Someone mentioned the "size" of Eurostars and implied this was due to their tri or quad voltage requirements. I was pointing out that the size of Eurostars (presumably they were refering to the length of the powercars and the fact that the outer end of the 1st trailer is also powered), is far more down to the high power output requirements of a Eurostar powercar than the need to work of multiple voltages. I gave an explanation for one of the reasons for the high output as being the length of the train, which is rougly twice as long as a TGV. I only brought up half sets to say that a single Eurostar halfset is about the length of a TGV but has one powercar. I didn't ever suggest they ran alone, which is irelevant to the point.

The use of PLC's dont aid the size. Modern technology can produce more power then the 373 and be alot smaller. The technology is old and that is the determining factor for the size of the power car. Most TGV's have two BM's per power car only, same as the eurostar, except the eurostar has an extra BM at the front end of the R1's, to overcome the extra weight.
In the power car everything is similar size to any other TGV.
 

cav1975

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71001/E5001 is still lurking in the National Railway Museum collection somewhere. It could probably be used to test the infrastructure of your proposed 750v DC 3rd rail overhead extension of a 3rd rail system as, based on previous experience such as the domestic trains on HS1, the infrastructure will be ready long before the rolling stock.
 

apk55

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For many of applications talked about a Bi_mode locomotive could be a solution. Bombardier are offering a Bi_mode version of their TRAXX loco with a low powered "last mile" Diesel engine for shunting.
If a UK loading gauge version could be produced ( and there is talk of that already for other applications ) it would be a useful general purpose freight loco. I would suggest a 25KV (5MW), 750V (2MW?) and diesel (500KW?) design
 
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For many of applications talked about a Bi_mode locomotive could be a solution. Bombardier are offering a Bi_mode version of their TRAXX loco with a low powered "last mile" Diesel engine for shunting.
If a UK loading gauge version could be produced ( and there is talk of that already for other applications ) it would be a useful general purpose freight loco. I would suggest a 25KV (5MW), 750V (2MW?) and diesel (500KW?) design

Why a lower rating for 750 V dc?
 

RobShipway

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The Eurostar power cars are also down to the fact that when they were being designed, it was thought best not to have any of the electrical motors on the coaches as this would cause there to be more weight and it would drag the speed down.

Of course now you have trains like the Siemens IE400 where the motors needed and pantographs can be included within the design of the coaches of the train.
 

Peter301184

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The Eurostar power cars are also down to the fact that when they were being designed, it was thought best not to have any of the electrical motors on the coaches as this would cause there to be more weight and it would drag the speed down.

Of course now you have trains like the Siemens IE400 where the motors needed and pantographs can be included within the design of the coaches of the train.



thats wrong. eurostar have two traction motors per half set on the front end R1 bogie 3. Thats four traction motors on trailers for the whole set.
 

apk55

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--- old post above --- --- new post below ---
Why a lower rating for 750 V dc?

It is only suggestion at this stage. While the 3rd rail supply system may theoretically be able to deliver up to 4 MW i suspect this is a short term rating. A locomotive would be expected to work at that power continuously. Also I hear there are problems with the class 92's collecting that level of current. It is only a suggestion at this stage.
 
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Holly

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For many of applications talked about a Bi_mode locomotive could be a solution. Bombardier are offering a Bi_mode version of their TRAXX loco with a low powered "last mile" Diesel engine for shunting.
If a UK loading gauge version could be produced ( and there is talk of that already for other applications ) it would be a useful general purpose freight loco. I would suggest a 25KV (5MW), 750V (2MW?) and diesel (500KW?) design
That would work well for long distance boat trains to Birkenhead 12 Quays (for Belfast and Dublin). That is to say after Crewe-Chester electrification if that happens. Terminating at Rock Ferry on days that there is no sailing (during a bad storm).
 
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