Re: Fate of 85/86 class

[Greg Rudd <grudd@mail.usyd.edu.au>]

Maurie Daly wrote:

> In article <389C4065.629@start.com.au> Dion Williams <onamission@start.com.au> writes:
> >From: Dion Williams <onamission@start.com.au>
> >Subject: Re: Fate of 85/86 class
> >Date: Sun, 06 Feb 2000 02:23:17 +1100
>
> >John McCandless wrote:
>
> >> Also, the overhead lines restrict any expansion of the loading gauge.
> >> Double-stack containers and the like.
>
> >Not sure how that would affect whether electric locos are used or not,
> >given that the suburban and interurban fleet need the same network and
> >reconfiguring them would be hugely expensive. The fuel must be cheap
> >indeed if say three NRs working a freight over the Blue Mountains is
> >cheaper than two more powerful 86s.
>
> >Dion
>
> Err,little confusion here , the 85 / 86s are nowhere near as powerful as an NR
> or indeed an 81.
> Please dont confuse as a lot of people do horsepower with pulling power.
> Horsepower is simply a measure of the power output of the main prime
> mover with a small reduction due to the non perfect efficiency of
> the rectifiers and traction motors .
> The pulling power is determined solely by the gearing ratios of the traction
> motors and by their design , ie the amount of iron in the motor, the guages of
> copper in the armature and the field coil current.
> Pulling power is measured usually in either Kn (kilo newtons or Lbs).
>
> here are a couple of examples.(these are continous ratings)
> 81 class 75730 lbs at 19 km/h.
> 85 class 49910 lbs at 45 km/h.
> 86 class 49887 lbs at 45 km/h.
>
> Railpages loco info has tractive effort figures for most Aus locos and its a
> very useful source of info.
> One of the more interesting bits of info on loco page is the fact that for 22
> tonne axle load locos ,the most powerful loco (ie most pulling power) is the
> SRA 82 class.
>
> MD

Hi all

Also another couple of factors that don't weigh in factor of the 85/86 classes is the
diameter of their driving wheels which are a lot larger that the diesel classes which does
not help their low speed tractive effort. As well the 85/86 classes do not have any
sophisticated traction contol equipment  such as super series or microprocessor control
that the later diesel classes such as the 81/82 and NR class.


See ya.

-greg