Model railroad wiring is one of the most critical and sometimes, most frustrating chores required to build a smooth-running layout. Electrical current is necessary to run the trains, operate the switch machines, light the buildings and streets, rotate the turntables, and energize any number of other accessories. If you are new to the hobby and have not yet been initiated into the joy of wiring your first turnout or trying to figure out how to get 1.5 volts out of a 12 volt power supply, click here for basic electronics for model railroad wiring. Before wiring your railroad, establish a set of guidelines such as the following:
(1.)-Minimum wire size. – The AWG (American Wire Gauge) rating shows that the smaller the gauge number, the higher the current handling ability of a wire. For example,-number 10 gauge wire will handle more current than number 16 gauge. For low voltage (12 VDC) used on model railroads, wire gauges of 14-16 gauge are recommended.
(2.)-Solid or stranded wire?-Stranded wire is used for the majority of wire runs and should definitely be used where flexibility is needed. Short sections of solid wire can be used for soldering power feeders to track rails A tip here about wire-buy large rolls ( 500’ or 1000’ ) of your main size The cost saving is significant.
(3.)-Use color coded wire and label wires with numbers where needed.
(4.)-Keep wire runs neat and bundled properly.
(5.)-Observe proper soldering techniques.
(6.)-Divide your wiring into power districts.
Some wiring tutorials suggest soldering rail joints when using 3’ sections of flex track. The advantage is that the track then becomes an additional electrical conductor. In certain locations, such as a long bridge where track joints are required and feeder wires cannot be easily installed, soldering the joints may be necessary. The disadvantage is that model railroad track, under conditions of variable temperature and humidity, will expand and contract. The result is out-of-gauge track sections. My preference is to use rail joiners and supply separate wire feeders to each 3’ length of track. Provide a small gap at each rail joint ( I use a piece of cardstock which measures about 1/32” as a gauge).
It is a good idea to test each section of track as you wire it-especially if a turnout is involved. The best way to do this is to run a locomotive through the newly-wired length and check for proper operation. Nothing is more frustrating than to spend all day wiring multiple areas of track only to discover later that a short or some other problem exists and now is extremely difficult to locate and repair.
Model railroads normally require a variety of power supplies to control such devices as switch machines, turntables, lights, and animation. It is good practice to use separate sources for each of these requirements. The most common voltage used is 12VDC but some popular miniature lamps operate at 1.5 VDC and require very small amounts of current. Electronic controllers for turntables and auto reversers usually come complete with plug-in power modules. Some types of switch machines need both positive and negative voltages for operation.
For convenience, model railroad wiring is broken down into the following sections:
Basic electronics for model railroaders
Model railroad control panel wiring