| For those interested in model toys, particularly that of | | | | attached to the common rail, with a second to go to |
| the model train, one thing they will inevitably come | | | | either the insulated rail of the oval or to the sidings in |
| across when commencing their hobby is the issue of | | | | order to be controlled. |
| how to wire their railway. | | | | The common rail system is a very popular one, |
| One of the most popular ways to do this is through | | | | primarily because it enables the system to pass on |
| the device called common rail wiring, the basic concept | | | | control from one of the packs to the other, with the |
| of which lies in always insulating the same piece of rail, | | | | model train on the track thus gaining power from the |
| while leaving the other one still connected. Sketch and | | | | right side of the front truck at the same time as it is |
| or draw a layout of your system that shows the dual | | | | getting it from the left side of the rear truck. Minus the |
| tracks while marking the outer and inner rails as "plus" | | | | common rail, the model train would otherwise regard |
| and "minus" respectively. In the example of an oval | | | | the insulated joint as a malfunctioning switch and would |
| track layout, this means that the outer rail will always | | | | thus then just stall on the track. Just be prepared for |
| be positive no matter where it goes, and the inner rail | | | | the possibility of the model toys surging unexpectedly |
| will therefore also always be negative. The benefit of | | | | fast when crossing over the joint! |
| this is, once you have insulated the inside rail on every | | | | One last point - remember to double insulate on the |
| siding (even those controlled via on-off switches), the | | | | section of the track where you require the train to |
| outer rail therefore becomes akin to common ground, | | | | reverse back on itself - this means that the positive rail |
| while the inner rail resembles hot switched lead. This is | | | | will suddenly run smack bang into a negative rail, and |
| why this method has become known as "common" rail | | | | thus an insulating gap and plastic joiner are essential |
| wiring for the model train. Two different power packs | | | | here. A DPDT (double-pole, double-throw) switch will |
| are recommended for this system, both insulated from | | | | be required for this operation. |
| each other (such as in the cases where an oval is | | | | Aside from this, however, the common rail wiring |
| inside an oval), as they can then have the ability to | | | | should be the best solution for your model train toys |
| control different areas of the layout in the same | | | | system. |
| instances. Both packs need at least one wire to be | | | | |