Eddie Oliver wrote:
Maikha wrote> > The signal was full red, but then the bottom light on SY54 had lit up
> > and the loco hauled train slowly moved out, on its way to Flemo.> > Can anyone out there give abit of a word on this?
Presumably the "bottom light" you referred to was yellow, i.e. a "shunt"
light which authorises a train to pass the signal prepared to stop short
of any obstruction.Signal-spotter wrote in response
> Could be a subsidiary shunt if it showed yellow or a Low Speed if it
> showed green, although the latter is generally mounted in the bottom
> head.The signal in question, like the other running signals in Sydney Yard
north of Cleveland St, is a single-light-indication type. As far as I
can recall on a quick mental scan, none of the single-light signals in
Sydney Yard are fitted with low speed indications.
There are no provisions within the NSW signal standards to have
a low speed on a single light signal. The closest thing to a low speed
on a slcl signal is the close-up. eg 33.3 signal on the down main at Campbelltown.
The signals within the Strathfeild/Lidcombe area do not have low speed indications that are seperate from the bottom head. ALL signals within this area that have low speed indications on them form part of the main head i.e. the fourth light on the bottom head. The additional lamp below the main heads on these signals are call-on indications and not low speeds as first thought.Your generalisation re low speeds usually being mounted in the bottom
head (of double-light signals, presumably) is interesting, in that the
Strathfield/Lidcombe area is particularly rich in signals where the low
speed lights are on separate units rather than being the lowest light in
the lower main head. I don't know why - can anyone cast any light on
this (no pun intended)? One might theorise that they were designed to be
close-ups rather than low-speeds (and someone changed their mind in the
design stage) or maybe simply someone decided it was cheaper that way,
but does anyone know definitively?