Resistor Wheel Sets

When using block control on your layout or when using any other type of train on track indicator, then the most popular technology to use is where the sensor looks for a small current passing through the feed wire.

For DCC this will be the chip that is taking power all the time, even when the train is not moving. For DC there is a need to add a small bias current such that the when loco remains stationary it is pulling a small current and so can be detected.

All this is fine for when the whole of the train is in the same block but if the train is longer than one block and the carraiages have lighting then they will also be detected in the next block but if it has no lighting or its a goods train then you will need to create a small current for at least the last wagon or brake van.

This could be a small LED tail lamp or glowing fire but you will need pickups to make this work. A good way is to convert some or all of your rolling stock to have a resitor wheel set, this You Tube video shows you how;