Model railroad wiring is what makes the electricity flow in your train display so that the engine can pull its cars and so that houses, buildings and streetlights can glow with warm, realistic lighting. Modern wiring is even so sophisticated that it can run a miniature camera atop the engine as it chugs through your display. The possibilities are endless: Just think of all the electronics in real life and integrate them into your display.

Wiring Basics

Model railroad wiring can be a complicated endeavor; therefore, if you are new to wiring, it’s best to consider asking for help from a friend, consulting a resource book or even simply purchasing a pre-wired baseboard. However, a basic understanding of model railroad wiring will get you as far as you need to go when first starting out.


One of the first components of model railroad wiring is a controller. Controllers, or transformers, run the voltage that determines the speed of the train’s engine. The controller also delivers the necessary power for accessories and can be turned on and off with a switch. On the controller itself, there are direct current (DC) terminals and alternating current (AC) terminals. The engines are generally controlled by the DC terminal, which can change the polarity so that the train engine can reverse direction. Accessories such as lights in houses or street lamps are usually controlled by the AC terminal, and wiring can run from underneath the board to each accessory as needed. Both DC and AC terminals are typically marked on the controller so that you can easily connect the wires.


Another component of model train wiring is voltage. When installing lights and/or accessories in your display, make sure they are rated at the same voltage or slightly above the output of the AC terminals. For example, if you use a six volt bulb on a 12 volt terminal, the bulb will have a very short life. Also keep in mind that adding too many lights or accessories to the circuit can decrease the performance of your display, such as the train running more slowly than normal. In order to avoid overloading a large display, use two or more controllers as needed.

Digital Command Control (DCC)

With the digital age comes Digital Command Control, or simply DCC. This exciting advancement in technology enables an operator from a “command station” to feed the track a digital signal; this signal provides both power and control instructions to the locomotive which reads it with “mobile decoders.” One advantage of this protocol is that two locomotives on the same electrical track can be operated independently. DCC can also be used to control other accessories.

Avoiding Electrical Mishaps

Sometimes it may be inevitable to avoid mishaps when working with your model railway wiring; however, following a few basic practices can help improve your success. First, make sure that all connections are correctly wired and tight, as loosely fitting wires may not properly perform. Also, ensure that your train tracks are connected to the DC terminal on your controller. For most trains, if you mistakenly connect the tracks to an AC terminal, you may possibly damage your train’s engine.

Furthermore, to maintain continuity of your track and to support efficient wiring, make the track as level as possible and secure it to your baseboard. Debris like dust and dirt will accumulate over time, which can kick up inside of the train’s engine and may interfere with performance. Therefore, occasionally clean the track with a soft, clean cloth using a contact cleaner or denatured alcohol. Keep in mind that denatured alcohol is highly flammable and poisonous; therefore, use extreme caution when handling.

Source by Johan Bentley