Re: Pantograph Operation - Melbourne
  Richard Youl

I don’t recall seeing anybody reply to this.

It looks to me like a basically standard break insulator, requiring the driver to cut power as the insulated material is almost certainly longer than the width of the pantograph.

Usually bridging insulators have V shape wings to pick up the pantograph while it is still on the approach side section of overhead. These are quite common on the railways but there could be other designs more recently developed which I have not seen. I’ll have to keep an eye open in Melbourne next month.

Regards,

On 9 Jan 2019, at 9:01 pm, ma261065 mickalex@...> wrote:

Is this a breaking or no-break insulator (on Queen's Bridge)?

> On Wednesday, January 9, 2019 at 9:37:33 PM UTC+11, Matthew Geier wrote:

>

> On 9/1/19 9:25 pm, 'Richard Youl' via TramsDownUnder wrote:

> > As the length of the insulating material in the centre of the SI is greater than the length of the pantograph head to avoid bridging the two sections, it is necessary to cut power to avoid an arc which burns the insulating material and adjacent metal.

>

> I understand there are both breaking and no-break SIs and that no-break

> ones are becoming more common. With 10kw or more air-conditioning load

> even cutting off will still draw an arc.

>

> And with the interruption to power, the air con compressor stops and has

> to go through an unload - restart cycle that takes a minute or so.

>

>

>

> > Regards,

> >

> > On 9 Jan 2019, at 7:48 pm, Ronald Besdansky shrdlu....@...> wrote:

> >

> > Are drivers still required to cut-off at section insulators and H-crossings?

> >

> > I remember Green Men noting down the numbers of trams drawing an arc as they crossed Swamston St in Collins St - not wanting to lose momentum for the climb beside the Town Hall?

> >

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