Here are a few photos of part of the inside of a fiberglass signal bungalow similar to the one shown near the cantilever signal. This is from a different location than the cantilever signal location but the interior is of the same design. This is the terminal board where the underground cables come in and are terminated. These are the plug in signal relays made by Safetran but based on a design of General Railway Signal Co. This shows the electrical service equipment, one of the battery charging rectifiers and the combination air conditioned/heater. The electronic portion of the computer assisted dispatching control system is not shown.
I don't think anyone saw this before it was displaced by another subject so am bringing it back to the top.
Thanks for bringing this back to the top, Gil. Those are truely awsome pictures. It is rare to be able to see the inside of these boxes.
Looks a lot nicer in there than in most engine cabs. LOL Might get me thinking about switching crafts!
Gil, Looks like they used nice wood in there! You have any idea what they used? Very interesting photos indeed!
This is one of the fiberglass houses which are quite different from the steel or aluminum houses. Those are not paneled inside but have the same type racks for the relays. I will try to find a photo of one of those.
I find it interesting even with today's technology that there is that much equipment in there. I guess in another 25 years one day there will be a box the size of a pack of cigarettes mounted on a pole nearby!
That location was controlled by a dedicated phone line connected via a modem to the electronic control unit. All the plug in relays you see are part of the fail safe system which controls the individual signals, power switch machines and other equipment. All of the fail safe equipment has to meet standards regulated by the Federal Railroad Administration. A fail safe system means that the failure of any one component will cause the system to go to it's most restrictive condition or all signals at stop. If my memory is correct this location controlled a crossover plus four two unit controlled signals.
Missed it as well, Gil, thanks for bringing it back. But I can't see the images? well, there you go... they came up eventually!
Those are very interesting pictures of something we never get to see. Thanks for the enlightenment, Gil
I love the tech stuff that most folks never get to see. Far cry from the old armstrong towers, eh, Gil?
As Johnny Trains suggested there is a system that almost eliminates the relays to control a cTc control point or interlocking. It is a GE Transportation Systems Vital Harmon Logic Controller (VHLC) and you can read about it at this site. https://www.getransportation.com/general/apps/global_signaling/Products/Detail/vhlc.asp It was designed by Harmon Electronics who were then taken over by GE. The units that were installed when I was working controlled and end of siding location or a double crossover location but that was over 10 years ago. My how time flies. There are other companies that make similar systems but I am not familar with them.
Other systems readily available are Microlok manufactured by Union Switch and Signal. SSI manufactured by Westinghouse and Alstom all these systems are known as CBI or computer based interlockings.
Gil, theres a couple of the Vaughn-Harmon VHLC interlockings in use in the upper reaches of the East Anglian Region of the UK, controlled from Trowse Swing Bridge Signal Box. I've just done some work adding TPWS to signals there. The UK hasn't taken to it, though, and still prefer the home grown SSI system jointly developed by British Rail, GEC-Alsthom (now Alstom) and Westinghouse. Paul, there's also ETRMS by Alstom and an Italian system that was being eyed up for the West Coast Mail Line renewals over 'ere. That bungalow looks like a basement games room with all that panelling! As trick as it is I think I'd spec light coloured walls to make it easier for the maintenace techs fault find and the construction lads to finish.
All of those bungalows were wired in the signal shop except for the cables to the various signals, switches etc. There was a door behind the terminal board which made it easy to install the cables. I found the maintainers appreciated the panelling and did a better job of housekeeping than in the conventional bungalows. Jim - I had not seen a mechanical interlocking for over 20 years until I went to Australia in 93 and saw a few there. They were being replaced then and I imagine Paul could tell us all are gone now.
