From:TramsDownUnder@... [mailto:TramsDownUnder@yahoogroups.com]
Sent: Thursday, 20 April 2017 1:27 PM
To:TramsDownUnder@...
Subject: Re: [TramsDownUnder] World Class Again

On 20/04/17 12:09, 'Noel Reed'noelreed10@... [TramsDownUnder]
wrote:
>

> Would water on a flooded APS power rail be likely to boil beneath a

> stranded tram when the driver attempted to start ?


This hasn't happened in Bordeaux, never seen any reports as such, but
they don't get downpours like we do.

So we will just have to wait and see what happens in a real Sydney downpour.. N R.

> Similarly, could there be a fire beneath a stranded tram due to arcing through a discarded newspaper on the power rail ?


Some one managed to get a bicycle (frame ?) under a tram with resulting
fireworks.

The Dubai installation apparently has brushes ahead of the pickup shoes
to sweep sand of the power rail. Presumably it isn't an electrical hazard, but would make the wear rates of the shoes and rail quite
excessive. Note the shoes are in pairs so in theory one should always make contact even if paper or other rubbish temporarily insulates one.

The trams will be double ended [bi directional] so brushes would be in front of and behind the pick-up shoes. Would the ‘rear’ brush contacting a power rail still ‘alive’ cause a CB or fuse to cut power ? How would wear of the brushes be monitored so that they always contact the rail. Would they retract to avoid wear on the road surface and on ballasted track when the tram reaches the proper overhead trolley wire and be proved to have re-lowered when returning to the APS sections on the return journey ?

Noel Reed

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Posted by: Matthew Geier matthew@...>

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