What is a switch box for?
I have seen them in the ratio catalogue but I would like to know where on a
railway they would go, what they were for and when were they introduced?
Thanks for all the replies on the ash question too :-)
'Twas Mon, 5 Jan 2004 16:14:45 -0000, when "piemanlarger"
decided to declare:
If it's one of those steel grey cabinets, they contain all the fuses,
relays etc for track circuits and signals. One is normally at each end
of a track circuit in a lightly-tracked area. In an area of dense
trackage (eg. Clapham Jct) they are incorporated into a relay room.
If it's not those, sorry!
I think you mean the large grey cabinets that hold track-circuiting
gear and their power supplies. The relays inside are each about half
the size of a car battery, so you can see they can take up a fair
amount of space. The relays are rather nice pieces of engineering,
designed to give long service, but are slowly being replaced by much
smaller solid-state devices. The boxes must have been around since
T/C was first used, albeit of wooden construction, so whatever period
you intend to model should have at least one box beside signals and
points. To my mind, they are as much a feature as signals, but very
few layouts seem to portray them.
In the trade we call 'em "locs" short for location cases. Relays are still
going strong, my employer (Westinghouse) has a large factory still in
Chippenham where 100s of the things are produced each week and/or repaired
every week. New stuff like TPWS that comes out does, as you say, use solid
state equipment, but for it to interface to the existing gear it still needs
To see what a relay looks like, go to this link:
click on relays. The "Q" type is the standard BR930 series of relay,
thousands of which you pass by on the lineside every time you take a train
journey. "Q" type relays are a result of the BR standard set in the 1950s.
Not much use I know, but gives a little backgroud information.