Back in the 90’s, I was taken to West Brunswick substation by Craig Tooke to watch the glass bulb mercury arc rectifiers “levitate” as he called it.

When a couple of then new B class trams went through the section, the load governed cooling fans sounded like the Spruce Goose taking off as a myriad of load arcs raced around inside the bulbs. It was a Hewittic rectifier rated at 600kW (1000A at 600V) and it was a hot summer day. The ammeters were off the scale on the rectifier. Good times! A link to the history is at West Brunswick Mercury Arc Tramway Substation | www.engineersaustralia.org.au https://portal.engineersaustralia.org.au/heritage/west-brunswick-mercury-arc-tramway-substation

By the way, has anyone heard how Craig is going? The last I heard he was very unwell and in a nursing home.

Cheers,

Mick in still very cool Brisbane

From:tramsdownunder@... tramsdownunder@...> On Behalf Of Andrew C
Sent: Wednesday, 17 August 2022 4:56 PM
To:tramsdownunder@...
Subject: Re: [TramsDownUnder] Re: Power substations

Balaclava Road, 3/3a and 16, was short of power with a tram or two more along the way, perhaps because of late running, the power could be knocked out. With only every second tram being generally rostered to be a B class on 3/3a, I think this is still the case.

Andrew.

On Mon, 15 Aug 2022, 10:32 am Mal Rowe, mal.rowe@... mailto:mal.rowe@gmail.com > wrote:

On 15/08/2022 09:53,peterm...@... mailto:peterm...@gmail.com wrote:
> 1500A on a 600V overhead, is not good in terms of voltage drop. Ive

> not been to Melbourne for a while, is it still a single contact wire,

> or are there dual contact wires and additional feeder wires like

> railway approach to reduce voltage drop?

>

There are multiple feeder cables throughout the system and no places
that I am aware of where there is noticable voltage drop.

I was told at a safety briefing by Yarra that the trip current from a
substation is usually set at 2500A - meaning that up to 5000A is
available in a typical section fed from both ends.

There are no double contact wires that I am aware of, but there are
places where an extra set of contact wires is hung on the overhead as
feeders. You can see them in my pic at: https://tdu.to/i/52233

The light rail lines to St Kilda and Port Melbourne still have the
heavier contact wire and catenary from railway days.

See my pic at: https://tdu.to/i/39803

Mal Rowe - who once knew a bit about Elec Eng