RE: GCLR2 Trams Today
  Noel Reed

There was a tram to tram accident in Melbourne about 2010 when a tram turned right across the path of another tram heading on the straight.

The accident report showed that there was no coordination between the tramway point position indication and the road traffic signals.

Some fans have criticised the extensive tramway signalling once used in and around Sydney, but at least proper interlocking ensured that conflicting indications were not displayed on the signals.

Noel Reed.

From:TramsDownUnder@... []
Sent: Friday, 10 November 2017 6:33 PM
Subject: Re: [TramsDownUnder] GCLR2 Trams Today

But surely the VETAG system - or whatever name it goes under these days - should ensure that the points are set for the route the
tram is travelling on, and should also warn the driver if the points refuse to obey the commands.

If two trams run into one another because one driver has ignored the setting of the points, both drivers are surely at fault. The
driver who should have kept straight but turned is at fault because he did not check the setting of the points; the other driver
should have seen that he was forbidden from proceeding because the points were set for a movement across his tracks. Or is there a
missing indicator here?

Consider the turn from Spencer Street into Collins Street. Uphill (northbound) there should be an indicator clearly showing the
route the points are set for. This should be actuated from the point blades, and the point blades should not be alterable while a
previous tram is passing over them. They should receive the actuating signal from the tram, store it, and ensure that the action is
taken when it is safe to do so. Downhill the indicator should prohibit passage if the up points are set for a turn, or a westbound
Collins Street tram is given authority to proceed into the intersection.

Much though I disagree with Noel about the issue of interlocking at tramway intersections, I am coming to think that at certain
situations a full interlocking is desirable. This is provided that it is totally automatic, reliable, and acts on receipt of
signals received from the tram's VETAG system.


Dudley Horscroft
----- Original Message -----
From: "Mal Rowemal.rowe@... [TramsDownUnder]" TramsDownUnder@...>
To: TramsDownUnder@...>
Sent: Friday, November 10, 2017 5:48 PM
Subject: Re: [TramsDownUnder] GCLR2 Trams Today

> On 10/11/2017 5:19 PM, Robbie Smithzoqaeski@... [TramsDownUnder]

> wrote:


>> I think Melbourne points indicators only show the the direction the

>> points are set for, except on some new installations that are

>> interlocked which use a different type of indicator [2], but someone

>> with a copy of the rulebook would have to confirm this.

> Thanks Robbie, that makes sense.


>> I personally think the compulsory stop rule is an archaic throwback to

>> earlier times, and new and upgraded points should be fitted with

>> locking devices with route detection.


> Although it is a long standing rule, it has been enforced much more in

> recent years after a couple of head-ons / side-ons caused by drivers not

> noticing that the points were set for the curve and running into a tram

> heading in the opposite direction. So the simplest solution is to force

> drivers to stop and check. Approach locking would not solve that

> problem if drivers ignore the signal and the setting of the points.


> Mal