EPTC The East Penn Traction Club

Model Trolley Layout Modules

Appendix A

Use a 'Black Box' to Add Module Block Control

The ideal modular traction layout has block control of every track segment, so that any car can be stopped individually. The 'near' and 'far' block wiring in our module standards offers greatly improved layout operations. When followed fully, this scheme enables more cars to run at one time, and lets them run more smoothly and on closer headways. Each loop, turn back, or other module designed as a control point should be built with four toggle switches for every track interface. These switches remotely control tracks on other modules extending off that interface.

Here is a way to add these block controls to any module. It can be used where a control panel was mistakenly built without the extra toggle switches; when more interface tracks are added to an existing module; or to turn any ordinary module into a control point. It was named the 'Black Box', since that’s precisely what it looks like.

The Black Box is a special module cable. To build one, get a box to mount four toggle switches (such as the smallest black 'project box' at RadioShack), plus four single pole, single throw (SPST) toggle switches, two standard male 6-prong connectors, and some 18-gauge or larger wire. Set the cover plate for the box aside. Use the box upside-down, leaving the bottom open so the box can easily be C-clamped to any module side frame. Drill two holes in one end for the wires.

One cable end will supply power to the Black Box. Run rail power wires from pins 3 & 4 on one male connector to pins 4 & 3 on the other male connector, passing the wires in and back out of the box. I made my wires about two feet long from box to connector. Now run wires from pins 5 & 6 on the supply-end connector to the toggle switches. Each wire connects from the pin on one side to the 'near' and 'far' toggle switches controlling the track on that side. Remember that the connectors will be used with the prongs facing upward!

The other, 'controlled' cable end needs wires run from the “near” block toggle switches to connector pins 6 & 5. Similarly, wires from the two 'far' block toggle switches go to connector pins 2 & 1. Label the toggle switches 'Near' and 'Far' and the project is done.

To use the Black Box, plug the supply-side connector (it has four wires) into the socket on the module you will be controlling from. Plug the other connector (with six wires) into the adjoining 'controlled' module. Finally, clamp the Black Box to the module edge with a small C-clamp.

Now a control panel can be installed anywhere in seconds! To make an ordinary module into a control point, hook a power pack to the module’s internal rail and overhead feed wires, and install a Black Box cable for each interface leading from the module.


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