Re: Alstom for Hillside/Yarra tram [Melbourne Aust]

[matthew@mail.usyd.edu.au (Matthew Geier)]

In article <OTrW4.1713$_Q6.692513@news0.optus.net.au>,
David Bromage <dbromage@fang.omni.com.au> wrote:
>Michael Kurkowski (mk@netstra.com.au) wrote:
>> Evad Rehtona <davemclAXETHIS@iprolink.co.nz> said:
>
>> >I have never really been able to work out what the 4D is from the
>> >newsgroup. Is it the sole (Sydney style) Tangara train in Melbourne, or
>> >what?
>
>> In basic terms it's a Tangara with different dimensions, mainly to fit 
>> within the Victorian loading guage. Many parts between the two should be 
>> interchangable (seats, traction equipment,
>
>The traction control is very different. Assuming you didn't a bogie
>exchange, you couldn't run a 4D in multiple with a Tangara. The 4D was
>designed to run in mulitple with a Comeng.

 Probably only software and a different pin-out on the coupler. I rather doubt
the traction package is totaly different, just different 'tuning' for the
different rolling stock it has to interioperate with.

 4D was built in the Tangara body building jigs. While it wasn't exactly
the same size, and the body structure had to be run through the computers
again, it is a Tangara deriviative, and not so completely different that it
needed its own production setup. I think that was the idea. To make a DD train
for Melbourne that had as much in common as possible with the Sydney version,
then horror of horrors the 2 systems could pool certain spare parts! :-)

 I think the 'pods' are the same, so Air-Conditioning, traction and auxillary
pods were interchangeable. The TMS systems are probably also the same computer
just with different software, that would mean lots of those parts are 
interchangeable, just make sure it had 4D software loaded and not Tangara
before replacing the TMS CPU board!

 CityRail however wouldn't want it for the same reasons Melbourne doesnt want
it, the mechanical and body differences would make it a pain to maintain even
if all the other systems had Tangara software loaded.

 Look what happened to 8650. Same traction system as the other 49 86 class, but
the tri-bo running gear continually confounded the fitters at Lithgow depot and
it spent most of its life sitting around waiting for a team to 'have time to
look at it'. The fitters naturally took other jobs first that they could get
out of the way quickly instead of delaying the entire maintence program while
they stuffed around with the 1 off.