Bus wiring under bridges

[Melchoir]

Small question...Do you continue your bus wiring under long bridges to keep the circuit complete in DCC ?

Thanks MIchael

[Texas Zepher]

Melchoir

Small question...Do you continue your bus wiring under long bridges to keep the circuit complete in DCC ?

The short answer is, yes.   But the longer answer is that the bus usually goes under the river too. 

There is a bus wire under the bridge/river in the photo below.

[selector]

It depends.  What sort of schematic do you have that will ensure you can get reasonably short feeders from your bus of any configuration up to the rails?  There is no reason to continue the bus under a long module of, say, 8 feet, if it also reaches near the other end coming from the other direction.  IOW, if you T the bus from the central processor, stop the one end at the edge of the long module-with-bridge, and have the other end run up to or just a bit under that module, simply run a pair of feeders from the tip that is closest to the center of the module.  That is the near-ideal solution.  The ideal solution would be to run the bus uninterrupted, but only if it makes abundant sense to run it uninterrupted.  Remember that feeders can be as long as three or four feet, provided they aren't feeding another 10' of rails.  That configuration could result in voltage losses that degrade performance noticeably.

Crandell

[Phoebe Vet]

My bus doesn't run under the track.  It runs from module to module with all feeders coming off a swing down board at the front of the module.  It is about 30 feet long and has never been a problem.

[BroadwayLion]

To reach the rails in the middle of the span, you could just lay the wires next to the track on top of the bridge deck, after all, railroads have cables all over the place. If the line is signaled the signal cables would follow the tracks across the bridge deck. You could also do it directly under the bridge, but while that might look better, the railroad would put them on top of the deck where workers would have access to them.

ROAR

[Melchoir]

Thanks for your great suggestions. When I do it on the bridges themselves, I wll let you know how it went.

Michael

[maxman]

Melchoir

Thanks for your great suggestions. When I do it on the bridges themselves, I wll let you know how it went.

Michael

Are you really asking about the track feeders instead of the bus wire?  Typically the bus wires in DCC are pretty heavy gage (16, 14, or 12).  I don't think you want them going across your bridge.  Feeder wires are smaller, so maybe they would look good as cables along the track.