Class 701 'Aventra' trains for South Western Railway

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4REP

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Seems an odd choice as the power supply is not the strongest there.

Not usually that keen to have 10car 444s on that stretch so having a 10car 701 seems brave (even if it is fairly quiet line). Wonder how many amps a 701 can draw on full power. I thought I read it was rated at 4MW which is a hefty 5333 amps (but I might be wrong)
Isn't it 2 units together that can't be used west of Poole together. A 10 car 701 is one unit so must have less traction than 2 units married together(eg 2 class 444/450/442
 

Domh245

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Isn't it 2 units together that can't be used west of Poole together. A 10 car 701 is one unit so must have less traction than 2 units married together(eg 2 class 444/450/442
It may physically be one unit, but is essentially two 5 car units semi-permanently coupled in the middle
 

swt_passenger

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Isn't it 2 units together that can't be used west of Poole together. A 10 car 701 is one unit so must have less traction than 2 units married together(eg 2 class 444/450/442
The sectional appendix limits 450 and 444 to single units normally, but goes on to say that longer trains can run with special permission from the Electrical control room, “if conditions allow”, which presumably includes a possession for testing...
 
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I have seen lots of video coverage of these units being tested at 25Kv Am I wrong to assume they did at least 1run at 750V before delivery? Is there a third rail test facility?
 

hwl

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I have seen lots of video coverage of these units being tested at 25Kv Am I wrong to assume they did at least 1run at 750V before delivery? Is there a third rail test facility?
Yes at the factory at Derby and Old Dalby.
As suggested above the 10 car train might have tried to draw a bit too much current as the power supply in the test area is well known for being under powered.
 

Warrior2852

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Bombardier's test track at Derby to my recollection has third rail, fourth rail and OHLE, but I don't know how much 701 testing was done there, in Geoff Marshall's video there it was running on OHLE.
 

Fincra5

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I'm sure Bombardier wouldn't send a 3rd Rail unit out without testing that it actually works on 3rd Rail.
 

59CosG95

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It's been suggested elsewhere that the unit didn't fail, but a local substation did.
The route west of Poole (IIRC) is a bit of a power supply blackspot, so it might have been the case that the 701's power draw contributed to the substation's failure.
Emphasis on the word Might.
There's every possibility the substation's failure was caused by external factors alone.
 

spark001uk

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5Q20 lastnight from litchurch to ferme pk, then onwards 5Q24 this morning to Wimbledon pk depot, both cancelled, not sure why yet.
Interesting they're booked 5Q now instead of 6X. They were still down as GBRF loco hauled though.

On another note, is 002 still in Weymouth? It's gone from Jersey sidings on the diagram now.
 

Bald Rick

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5Q20 lastnight from litchurch to ferme pk, then onwards 5Q24 this morning to Wimbledon pk depot, both cancelled, not sure why yet.
Interesting they're booked 5Q now instead of 6X. They were still down as GBRF loco hauled though.
The 5Q’s are standard paths in the WTT. There’s one to Ilford and one to Ferme Park, and they can be (and are) amended depending on final destination. The headcodes are also changed depending on what is being moved.
 

Taunton

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The sectional appendix limits 450 and 444 to single units normally, but goes on to say that longer trains can run with special permission from the Electrical control room, “if conditions allow”, which presumably includes a possession for testing...
During the 2012 Olympics sailing in Portland Harbour the normal 1 x 444 was replaced by 2 x 450, complaints about the suburban seating but stated at the time that they could work electrically through to Weymouth where 2 x 444 could not, although I always suspected that 2 x 444, which are as long as 3 x 450, likely would not fit the platforms.

Weymouth and Dorchester have done very well to get a twice-hourly service direct to London with the best trains on the network, they are not substantial places and the trains are commonly very empty west of Poole at all times; it really is a Gold Plating to expect a power supply to support more than it presently does. A classic old-school Southern Region/NSE project.
 
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swt_passenger

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During the 2012 Olympics sailing in Portland Harbour the normal 1 x 444 was replaced by 2 x 450, complaints about the suburban seating but stated at the time that they could work electrically through to Weymouth where 2 x 444 could not, although I always suspected that 2 x 444, which are as long as 3 x 450, likely would not fit the platforms.
That would make sense, because the individual 444‘s power capping is higher than a single 450. I’m sure platforms 2&3 can take a 10 car though, because they berth them “end on” there overnight.
 

Goldfish62

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I don’t think anyone knows any more, but certainly replacing any 8 car services with 10 gives an instant uplift. I would however imagine they’ll go on routes with poor timekeeping to begin with though as hopefully dwell times will be reduced and improve punctuality. Look at how guard operated 707s fixed the shepperton line overnight.
Given today's announcement of the reduction in social distancing to "1m+" but with the acknowledgement that facing others presents the greatest risk I'd have thought that withdrawal of the 458/5s would be a priority because they have around 80-90% face to face bay seating.
 

hwl

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It wouldn't though. People are sat closer together with airline seating.
Studies have shown facing seating to have higher risk even if further apart (though when you include 2x depth of person the distance face to face distance is usually less than airline spacing). The "Facing" bit is important as well as the distance.
 

Goldfish62

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Studies have shown facing seating to have higher risk even if further apart (though when you include 2x depth of person the distance face to face distance is usually less than airline spacing). The "Facing" bit is important as well as the distance.
Exactly.

When I next travel by train I am avoiding face to face bays because they are riskier than airline seating.
 

Goldfish62

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airline seating with enforced spacing (i.e. every other seat out of use) is the way to do it. On that basis, I would have thought most of the legacy stock would fare similarly.
Not the 458/5s. They have hardly any airline seating, whereas the rest have at least 50%.
 

yorkie

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Please can we stick to Class 701s in this thread.

The forum has plenty of spare capacity for separate threads to discuss any other topics :)

Thanks!
 

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