Re: XPT's Reduced

[mauried@tpg.com.au (Maurie Daly)]

On Wed, 09 May 2001 22:53:50 +1000, David Johnson
<trainman@ozemail.com.au> wrote:

>On Sun, 6 May 2001 09:10:37 +1000, "Adam Dunning"
><adamdunning@start.com.au> wrote:
>
>>The cost of the power car or generator for HEP could be cost prohibative for
>>such a small service.  As far as I know, the XP carriages use some
>>multi-phase power system which is not your normal run of the mill 415v
>>3-phase.  Does anyone know what type of power is fed to the trailers?
>
>There is a variable voltage variable frequency 3 phase supply to the
>trailers which is tapped off an auxiliary alternator on the main drive
>shaft.  It is up to about 415V 50 Hz.  50Hz would be attained at 1500
>RPM.   The air conditioning units have a crossover system, not sure
>exactly how, but they seem to reduce fan speed when the driver goes
>from Notch 3 to Notch 4.   Maximum fan speed is achieved in Notch 3.
>As the supply is not constant, all sorts of problems are encountered.
>Only resistive ovens may be used in the buffet, and I believe all
>lighting is run from 120VDC, rectified from the supply, and regulated
>across the batteries.   Microwave ovens were trialled in the buffet,
>but due to the fluctuating supply, they kept exploding.   The sleeper
>cars have 240VAC shaving outlets.  These run off 120VDC via a 40W
>inverter.
>
>Things would be so much easier with a PHA power van providing constant
>415V 50Hz power!
>
>
>Open to corrections, of course.
>
>
>David Johnson
>trainman@ozemail.com.au
>http://www.ozemail.com.au/~trainman/
>------------------------------------
>These comments are made in a private
>capacity and do not represent the
>official view of State Rail.
>C.O.W.S. Page 11.

You dont need a power van per se , just a HEP generator like the CLPs
have or even like the Vline P class. 
They are very small and given that XPT consists seem to be getting
forever smaller a huge amount of capacity KVA wise wouldnt be needed.
Around 250 KVA would be heaps for a 6 car train , given that most of
the load is the air conditionong .
There should be enuf room in the XP power car where the rear door is .
The other option is a static invertor which takes variable voltage DC
from the main traction alternator after its rectified and converts it
into 415 V AC .
This is essentially how AC traction locos work.

MD