The Signalling Project IV

Well, we made it! The new raised track signal system was ready for the start of the season as promised. The winter months saw no let-up in activity, despite the often unfriendly weather, and the system was finally ready for testing, with two weeks to spare before Easter.

The main job to be completed during the winter was the installation of the control cabinet. We chose to site this under the footbridge, so that we could take the 230-volt power supply from the adjacent outdoor power point. A large hole was dug, shuttering was fixed, and plastic piping was laid in for the cable entries. Following this a raised concrete plinth was cast, complete with fixing studs for the cabinet. We made a template to position the studs, so that on the following weekend the cabinet simply dropped into place over them. The actual control panel, which had been built and tested off site by Tony Vereker, was inserted and fixed inside the cabinet. Several weekends were then required to wire up and label the numerous field connections - fortunately our colour coding paid off and we had no crossed connections. Bob Breeze then gave the cabinet a couple of coats of green Hammerite and it now looks very smart.

The treadle switches were adjusted to trip at 2mm depression, the inductive sensor was fitted to the traverser, and we were ready for testing. We never expected it all to work "straight out of the box" but surprisingly, this proved to be the case and I had the (totally unplanned) honour of driving the first train around the circuit under full signalling on March 12th.

With a few last-minute adjustments, the system was made fully operational for the first day of the season on Easter Sunday, March 26th. A test train made several circuits in the morning, and all seemed well.

However, during the afternoon, when some longer trains were in operation, it became obvious that we had not got things quite right in the station area. The station area comprises three sections, namely 7, 8 and 9. Section 8 (between the arrival and departure platforms) was deliberately designed to be as short as possible, but we had overlooked the fact that if the train length exceeds the distance between two treadle switches, the signal switching sequence will be upset.

This caused much head-scratching at the time, but it soon became blindingly obvious as to what the problem was, and the treadles were re-postioned the following weekend. What a wonderful thing hindsight is! Section 8 is still the shortest section on the line, but it can now accommodate a train with a total fixed wheelbase of 26'-6", which is long enough for a 5" gauge 4-6-2 and tender, plus three single passenger cars, with about 3 feet to spare.

Following this alteration, we had to revise our original plan for section 8 not to have a signal. The extended section length now requires signal RL8 to be in place, so I am afraid that the diagram I presented at the February meeting is now wrong! If anybody still has this diagram, please throw it away and refer to the one in the new Code of Practice, which is correct.

Having sorted this conundrum out, the system has been trouble free, or should I say the only problem has been with some of the drivers! We have had one or two "SPADs" (signals passed at danger) - usually in the station area when drivers have pulled forward without waiting for the train ahead to clear the section. This can often be the fault of the platform staff, calling trains forward without being able to see the signal aspects. Drivers, please ignore any requests to move forward if the signal is at danger, but move as soon as a "yellow" is received!

Passing a signal at danger not only gives two trains in one section, it leaves a red aspect which will not be cleared when the train moves on. The procedure for dealing with this situation is in the new Code of Practice, but is worth repeating here:

1. Track Steward must first make sure that the over-running train is clear of the treadle switch for the section which has been entered, and hold the train in that section.

2. He/she must then wait for the preceding train to clear the section, after which he/she must briefly depress the treadle switch behind the train which has over-run.

3. The signal system will now be restored to its correct sequence, and the over-running train can re- start when the signal ahead changes to yellow.

To complete the job, two final touches have been made. Tony has fitted each treadle switch with a guard, to catch any hot ashes and prevent them falling onto the switch and its wiring, and I have just finished fitting the signal number plates. These should ease identification, and we won't have to refer to "the signal over by the fence" any more!

Most drivers seem to appreciate the new signals, as they add a new dimension to what is otherwise only "tail-chasing" around a circuit. They are also proving to be popular with the public, who seem to enjoy seeing them change colour as the trains pass. It's also surprising how many small children have never seen full size railway signals, and refer to ours as "traffic lights". Bless them.

Well, that just about wraps the project up, and two-and-a-half years' work is complete. Time will tell whether the system proves reliable, but the early signs are good. It goes to show that with a positive attitude and determination, things can be made to happen at the CPMR.