I'm stumped by my most recent wiring problem. I'm wiring for DC two cab control, using common rail wiring. I have several blocks all isolated properly by gaps in the rails. For the common rail the wires all come to a brass bus terminal which then is extended by one wire to the control panel. The power rail wires come to a dual barrier terminal strip where each block is isolated and then extended to the control panel individually for each block, then at the control panel power is routed through toggle switches.
I think I should add here that I had locos running through the different blocks correctly at one point, however I had a switch problem so pulled up the switch, fiddled with it to correct the problem (not a wiring problem, it was a point contact problem) and re-installed it. Now when I try to run locos on the track the power in that block doesn't seem to be there. I extended some wires from the back of the power pack and touched the rails in that block and the loco would run. I then used the same extension wires to touch the terminal points under the layout.
Here's the weird thing; when I touched a wire to the proper spot on the barrier terminal strip (power rail) and the brass bus terminal (common rail) the loco ran but only if I touched the wire to the exact post that this particular block is wired to on the brass bus terminal. If I touched the extension wire to another post on the bus terminal the loco would not run which doesn't make sense because all the posts on the brass bus terminal are all inter-connected by virtue of their connection to that terminal. Even weirder was that as long as I touched a wire to the exact post that this block is connected to on the brass bus terminal I could touch a wire to any of the other posts on the dual barrier terminal strip and the loco would run. I'm baffled because the loco should only run when I touch the wire to one particular terminal on the dual barrier strip, the wire going out to that block, since all the other blocks on that barrier strip are separated by gaps in the rail. It's almost as if each terminal strip is acting the opposite of what it's supposed to for this particular block only (i.e. the barrier terminal strip is acting as a common bus terminal because I can touch the extension wire to any post and the loco runs, and the bus terminal only allows the loco to run when I touch the exact post that this block is wired to, yet it should not matter which post I touch with the extension wire). And remember, the locos ran correctly before I pulled the switch up because of the point contact problem. I would be grateful for any suggestions/ideas that other veteran electronics gurus might have and thank you in advance for any help that can be offered.
I hope this description allows you to visualize how the wires are hooked up, but if it will help I can try and draw a basic diagram to explain the hook up. Looking forward to hearing your ideas!
Try taking the wire off the brass buss (common) and doubling it with another wire under its screw to see if the loco runs. Are both rails gapped? What make of switches (track) are you using? I would go back to that switch that you had to tweak to see if the power is passing through it for both rails.
Hi:
Thanks for the ideas. The problem is now solved. I more or less ended up doing what you had suggested, and am not sure what fixed it, but after disconnecting the wires at the buss and barrier terminals and at the control panel and then re-connecting them the locos run properly through all the blocks now. Thanks again for your input!