Re: Melbourne's Icons (was Melbourne's Anti-tram Lord Mayor)

[David McLoughlin <davemcl@REMOVEiprolink.co.nz>]

mcfergus@my-dejanews.com wrote:
> 
> In article <01be8bf4$9117f4e0$b8e78ec6@dialup.mpx.com.au>,
>   "Sams Workshop" <workshop@mpx.com.au> wrote:
> > The W, s contain the old CHOPPER DC drive system, ( you know the one that
> > blasts your car radio as you drive past.) which are course and electrically
> > very noisy.
> 
> Do the W's have a chopper traction system? I would have thought that they
> were resistance based, unless the traction systems were upgraded sometime in
> the last couple of decades.

The Ws most definitely do not use chopper control. They have the archaic
resistance/contactor system. Indeed, even the Z 1s and Z 2s have a more
modern form of this.

The first tram to be fitted with chopper control was Z number 5 in the
1977 as a trial. In 1983 it was conveterted back to the contactor
controls used in all the Z1s and Z2s. Chopper controls became standard
from Z3 number 116 and is fitted to all Z3s, As and B classes.

David McLoughlin
Auckland New Zealand