Why it can be a good idea to use decent size wiring and larger chunky toggle switches etc on a DC layout.
Incidents. If I am wiring for DCC, as cab control DC was so easy to trace any short circuits, I would wire up DCC like that as it saves so much time in tracing a basic fault. The number of times I left something small and metal somewhere across the track which caused a short! Yet one soon discovers that turning all track sections off, and then turning them on one at a time until the latest one turned on trips the controllers overload.... Why I ALWAYS preferred better quality DC controllers that gave either an auditable or clear visible indication of a fault, as some basic trainset controllers are awful to use! (Have a short, and one has to switch off at the mains, wait a minute. Switch back on with no visual or auditable indication if the thing is actually working or has tripped again! They are so frustrating! The better controllers one can visually see or auditable hear a short circuit as the controller displays this. (With DCC, I "Think" all DCC controllers display faults like this, but they do cost a lot more per its DC equivalent).
But decent DC controllers do help in fault finding, and add cab control (Which is not th same thing as common return though the two are used together if one also wires using common return "If" ones controllers are suitable), and one can trace faults so fast, as one knows exactly which area on the layout the short circuit is.
Examples of how better designed DC controllers show one has a short circuit.
Many have a separate LED style "Short circuit" warning light which illuminates if the controller short circuit protection has kicked in. With some of these, the LED indicator will flask to further attract ones attention. I believe Moorley controllers have this? My old H&M 3000 controllers have this feature on its display of 1980's style space age display!
Others, such as Gaugemaster, do it in a different way which is less visible but at least one can determine if there is a short, as one uses the "Track Power" LED indicator. The clearest way to do this is to turn the speed controller to max power (Or at least above half power) as it will then give a bright visual display (Best to ensure no locos are going to fly off the board while doing this!), then select a direction, and if there is s short, one will hear a "Click" and see the track power light turn off.
I prefer a separate overload light, though I used to be a bit "Jumpy" when it came to using my Dads old Hornby Dublo 3-Rail controllers when he had his 3-rail out, as those things gave a distinct loud sound and the light shone bright red if a short circuit occurred and it made me absolutely jump!
(A little caution about H&M 3000's. Lovely 1980's controllers which are a little hard to find now, BUT they do have early circuit boards that long plugs slot onto in their internal workings which as the years go by, these tend to tarnish or get dusty and will need a clean, so if buying these, they will need a trip to an electrician to be opened up to get these cleaned, and also checked over for safety. (Due to electrical complexity, some 3000's did fry their microchips, so buy them as a project if one comes across one). Once this work has been done and all is safe, working and passed, these controllers are lovely, though maybe a little complex. Probably the most complex DC controller one will ever come across as one can vary seemingly everything! All those sliders, switches and knobs just to move a single train down a single piece of track! Fun!
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