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TRACK & CONTROL

Here are a few photos and descriptions relating to the trackwork on Wibdenshaw.


During the planning stage, this single-slip needed to be situated on a baseboard joint.... not the most ideal solution, but works very well and keeps the rest of the track geometry looking right.


The storage yard on Wibdenshaw uses floating point blades for the exit trailing points. All polarity switching is duplicated from the entrance pointwork at the other end of the sidings by the use of relays. This works fine if you have no need to reverse, and cuts down the point motor and switching equipment by half. There's also no need to fit check rails, as the wheels do not need to be guided into the frog.


This diagram shows a fan of 4 sidings in the storage yard. Each road has a double pole relay, the contacts of which are shorted across the rails using the NC contacts. When the layout is switched on, there will always be one relay energised, which removes the dead short and provides a positive and negative rail (for the selected road) via the other three sets of relay contacts.


The outer rail of road 1 is common with the inner rail of road 2 (and so on for the other roads), acting as an extension for the live frogs. This does away with the need to fit auxillary switches to the point motors, as the relay contacts provide the switching function. LED mimics for the road selected, are provided from the rotary switch on the control panel.


Utilising this method of operation with a conventional variable DC controller, gives 8 separate sections within the 4 roads, with the use of only 2 toggle switches and a rotary switch. The extra sections of the rotary switch can be used to operate the point motors, using just one push button and a diode matrix.


This shows the control relays for 2 sets of 4 roads. The LEDs duplicate which relay (and road) is selected. The point motor relays can be seen in the background, and these are used to switch the power from the capacitor discharge unit. The diodes forming the matrix can be seen mounted on the board next to the relays.


Due to problems with stock traversing the curved diamond crossover at Pudsey Junction, it has been decided by the permanant way department to replace it with a switched crossover. This view shows the PW gang inspecting the crossover before work commences.


Full occupation of the trackwork was required for this operation, and all services were diverted via alternative routes. The internal rails have been removed, in preparation for the switched rails to be fitted (which can be seen on the BEV).


The new switched blades have been fitted into position, and the gangers look on and check alignment, before the chairs are fixed into position on the sleepers.


This is the situation at present, and normal running has been resumed until the following weekend, when the PW gang will return and finish off. The switched blades have been 'clipped shut' to allow temporary running. The tie bars will need to be connected to an equalising beam and point motor, which will be interlocked via the points feeding the crossover.