From: ajw@squid.mel.dit.CSIRO.AU (Andrew Waugh)
Subject: Re: Question: ATC <=> steam engines?
Keywords: ATC INDUSI SJ steam
Organization: CSIRO, Division of Information Technology, Melbourne
Date: Mon, 6 Apr 92 22:56:43 GMT

In article <1992Mar31.205230.24794@kth.se> d88-hba@nada.kth.se (Harald Barth) writes:
>Background: The regulations of the SJ (Swedish RR) are undergoing 
>some changes. In near future it will be required that EVERY leading
>engine on ATC (Automatic Train Control) territoty must run under
>ATC control. (There maybe some exceptions for switching movements 
>only). There is no ATC fitted steam engine in Sweden (yet).
>
>The JHRF (J{rnv{gshistoriska Riksf|rbundet ~= Hist. RR Soc. of Sweden)
>investigates how ATC can be fitted on a steam engine. A lot of equipment 
>(reciever, controls... ) can be adobted from scrapped class D (electric)
>engines. That leaves one special designed part: How to cut of the steam?
>
>These alternatives come to my mind:
>1: Valve in the smoke box. The smoke box is a ugly place! Valves
>   working under such conditions tend to be expensive.
>2: Servo motor on the regulator. What about clipped fingers when
>   the servo motor swings the regulator arm?
>
>I learned about the existance of some kind of ATC equipment onboard steam 
>engines of the DB (INDUSI) and Milwaukee Road, but I do not know how the 
>"interface" looks like. Anyone who does?

I doubt that any steam era ATC cut off power to the locomotive. As
you note, doing so would be extremely expensive and difficult. These
ATC systems acted only on the brakes. The brake system should be
capable of bringing a train to a halt even though the power might
be on!

If I was the JHRF, I'd try and negotiate with the SJ to see if they
would let you run steam locomotives fitted with the ATC system
applying only to the brakes. You may have to agree to run at
reduced speed.

If you want technical descriptions of steam era ATC systems, the
following books may be of interest.

%T Elements of Railway Signalling
%I General Railway Signal Company
%C Rochester, N.Y.
%D 1954
%K USA

	(A general description of the products of one particular
	Railway Signalling Manufacturer in the middle '50s. One
	chapter of the book covers Cab Signals, and another
	Train Control Systems.)

%T Railway Signalling
%E O.S. Nock
%I Adam & Charles Black
%C London
%D 1982
%K UK
%O ISBN 0 7136 2067 6

	(Compiled by the U.K. Institute of Railway Signal Engineers.
	Definitive text on the principles and practices of British
	railway signalling at the time. It includes a chapter
	describing the U.K. ATC system)

%T Automatic Warning Systems of Train Control and Trainstops
%S IRSE Booklets
%N 24
%A ?
%D ?
%I U.K. Institute of Railway Signal Engineers (IRSE)

	(A considerably more in depth discussion of the U.K. ATC
	systems. This booklet is probably of more interest to you
	than 'Railway Signalling' as it was published in the
	middle '60s and describes how the standard U.K. ATC system
	was fitted to steam locomotives. It also describes the
	older GWR ATC system which dates back to the early years
	of this century.)

All these books are, unfortunately, out of print. However, I would
be extremely surprised if the Swedish Railways did not have copies
in their technical library. You would be very likely to find copies
at large University or Reference library.

Finally, most signalling textbooks included a section on train
control systems. I'd look for those published in the '30s, '40s,
and '50s.

andrew waugh