Next came thoroughly testing the K 'n G Railplex.

Our first test was to confirm that the isolated outside rail and center power rail for a track block was properly connected to its controller and power relays.

To confirm proper track block connections and basic operation we used the "meter car" shown to right. It is a caboose with an AC volt meter connected to the frame and center rail pickup roller. It shows the voltage, if any, being applied to the track block's center rail.

Each separate train power source was set to a different voltage. The meter car was moved into a block. We could observe indicators on the controller for the track block to verify that a train had, indeed, been detected in that track block and that center rail power had been turned on (since there are no other trains on the layout, power should always be turned on.) By consulting the volt meter we could verify which power source had been switched.

Next, additional cars were used to verify that each block stopped a train when the block ahead was occupied. Then more subtle features like selecting a power level based on a train occupying a block two blocks ahead were tested. Track switch routing also had to be tested. Trains had to be routed to the track run that was most free.

This initial testing took a while, but we knew that finding a discrepancy during testing was considerably better than waiting for it to show up at some inconvenient time in the future. The testing revealed only a few wiring mistakes. We're good!

Now it was time for trains. We started with one train. After it successfully ran around the outer loop a few times ... we added a second. That was the real test.

Not only did the two trains never collide, the power selection feature kept them mostly on opposite sides of the outer loop. The picture to right, above, is the very first time two trains ran on the K 'n G Railplex.

Well, with that success we went crazy. We opened the full layout. The two trains ran over the entire track plan (we hadn't completed the "work" loop yet.)

We added a third train. Then a fourth ... until the picture to right with seven trains running ... perfectly.

We then tested with everything we could think of: short trains, long trains, slow trains, fast trains, at up to ten different trains running at once. We spend a couple of weeks playing with it and watching the trains. It is fascinating to watch.

We also did some work adjusting the relative power levels to various track blocks and verifying that track blocks were long enough to prevent a train from "coasting" through a block. We did adjust the length of two blocks a little bit.

Testing went so well we had to take the K 'n G Railplex to its first train show.