Quote:
Originally Posted by Bob_Sinclair
Completely agree that we are totally behind the curve...... by a country mile!
Seeing as you are shocked at this application, i take it this isn't the norm for electric locomotives?
Bob
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Well in my experience, mainline trains moving themselves around by using their batteries is the exception. I've never seen it in 21 years as a driver of electric-only trains
The trains I sign never did. Here's a list of them...
Class 313 (AC/DC) Moorgate/Hertford Loop/ECML (East Coast Mainline)
Class 317 (AC only) ECML & London Midland
Class 319 (AC/DC) Brighton Mainline / London Midland
Class 321 (AC only) ECML / Great Northern
Class 365 (AC only) ECML / Great Northern / Great Eastern
Class 377 (AC/DC) Brighton Mainline / London Midland
Class 387 (AC only) ECML / Great Northern / Great Eastern
Class 465 (DC only) SouthEastern Suburban
Class 466 (DC only) SouthEastern Suburban
Obviously traction motors require hundreds of amps to make them turn, and up until recently most electric train batteries have never had the capacity (or need) to do that.
I suspect that technological advances in battery capacity have made it possible to have a charge/weight ratio that is credible. Old fashioned Lead Acid batteries would be so heavy and take up so much space there wouldn't have been much room for passengers. If you look at the Tube's shunting locos, they're all batteries and motors!
On "traditional" electric passenger trains, batteries aren't required to pump out too much energy. When the train has been cut out (ie, completely shut down) they're used to raise the pantograph or lower the shoes , and then once the train is running on the juice they just provide 120v for the auxilliiaries when the current is interrupted by going over gaps (DC) or through Neutral Sections (AC).
They don't normally need to provide alot of energy. If a train is stranded without traction current you don't expect the batts to give you more than about 30 mins of emergency lighting and PA. And no heating, brrrrr.
My rant really was that whilst moving trains round without being juiced up is not completely new, it does seem to be on the increase. Nothing wrong with that per se, except that it shouldn't be necessary because the whole country should be wired.
Cheers, BW