Model trains (1 to XY) were powered by rails, one is plus second is minus and simple motor. You regulated the voltage. That means you can only power the whole track – all trains that are on the track.
But nowadays is some IC, that allows you to control every single train independently, even control other aspects of the train (lights and horn).
How does it works, that you can control every train station on track one by one only by power provided by tracks? (You do not have remote for every train, you have one master remote).
In: Technology
What you’re probably talking about is DCC (Digital Command Control).
With a traditional DC model train layout each rail has a wire running to it. A DC current is run to through those wires (so one rail becomes positive, the other negative) and the wheels of the model train conduct that power into an electric motor. To make the train go faster you increase the power to the rails, to make it go in reverse you reverse the polarity (positive and negative rail are switched).
With DCC the power to the rails is changed to AC power, or alternating current. That means the polarity keeps changing back and forth like a wall outlet. Unlike a DC layout you don’t change the power to make the train go faster and slower and you’re already reversing it many times a second so that won’t help to control the train’s direction.
Instead each train has a circuit board, called a decoder. One part of the decoder rectifies the power to provide a DC current for the motor and lights. Another part, a computer chip, monitors how quickly the polarity is switching back and forth. In order to control individual trains a DCC control system encodes messages by altering this switch timing which is interpretted by the decoder as 1s and 0s. Each train gets assigned a number and messages are sent along the rails telling a particular train to change its speed, change direction, or turn lights on and off.
Each train has it’s own circuitry to control the speed. Similar to how you might have a fan with multiple speed settings, but it’s still powered by the same voltage as everything else.
Pretty easy to do with a microcontroller and any kind of wireless receiver, Alternatively you can send signals through the tracks by superimposing a higher frequency signal on top of whatever voltage is providing power.
Latest Answers