Indeed there is a lot of wiring regardless of scale. With my large scale layout I have most my wiring terminated at the rear of the layout. For convenience I use Peg board (no holes to drill) for my wiring backboards. I’ve attached a couple photos.
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The above photo shows the major voltage feeds. The photo below is a large diode matrix that controls switch, signal, uncoupler motors and voltage to many LED’s.
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The photo below shows the wiring of my master control panel.
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All my wiring is color coded and backed up by a multipage spreadsheet. On the many occasions that Mr. Murphy and his pals the Gremlins have shown up, it’s been pretty easy to troubleshoot wiring problems.
@pianoforte , sorry I don’t mean to bugger up your log. Kurt got me thinking about all the colored wires that most visitors won’t see.