Under Construction: Incredible Baden-Baden layout from NOCH is being turned into an all digital N scale installation controlled by Marklin CS3. 

Oh, it is incredible alright, but how do I digitally control all those 21 turnouts?!

When it comes to digital control of motorized turnouts, there are options out there, but it is hard to beat Roco Z21 Switch Decoder 10836.

Z21 in the decoder name should not make you think that this is a product specifically designed for Roco's Z21 system. This decoder will work with any DCC controller; in fact this brief tutorial is how to use it with Marklin Central Station 3.

What makes 10836 particularly attractive is that it can operate up to 8 switches, it can be used on a Marklin layout, on standard HO layout or, as in this case, on N scale layout. Additionally, it can be operated with autonomous 12v power supply ($10 on Amazon), so not to drain current from the track. This is particularly important when having multiple trains, passenger coaches all lit up and trying to fire turnout sequence to set up a route - all at the same time.

And 10836 it is easy to program and use.   


As it happens, Marklin CS3 is an awesome DCC controller, perfectly suitable for a large and complex layout, such as this Baden-Baden.

So, how do you make it talk with Roco Z21 switch decoder?

Step 1 involves setting up all your turnouts in Marklin CS3 using DCC protocol.

Step 2 is an obvious one: connect CS3 to DCC track and run some trains to make sure all is well.

Now let's have a look at the z21 switch decoder.


Here are the connections for the switch decoder:

12 v Power supply (get one that comes with terminal connector).

It is worth noting that you may share single power supply across multiple decoders.

Take two wires connected to the track and connect them to DCC input next to power supply.

Connect turnout motors (standard 3 wires with black typically being center) to switch terminals 1-8. 

Once you program the decoder, all its terminals will receive sequentially incremented addresses. So addresses 1-8 for the 1st 10836 decoder, 9-16 for the second (if you so choose), etc.

This is how you program the decoder with your CS3:

- Make sure both power and DCC track connectors are in.

- Make sure Marklin CS3 is not in STOP mode.

- Press and hold Prog button on the decoder for about 3 seconds.

- Program light will bling indicating the decoder is ready to be programmed.

- On CS3 click to operate previously setup DCC turnout (say address 1).

- Note that Data light briefly lights up on the decoder, indicating the input has been received.

- Program light goes out and decoder should go back to blue Status light.

Congratulations, you just programmed 10836 decoder to operate digital turnouts with addresses 1 - 8.

Select that turnout on CS3 again and it should switch.   

If your installation requires multiple switch decoders, then read below carefully.

These decoders are programmed in ranges of 8.

If you program it with any turnout address from 1-8 (say 4), then the decoder will be set to operate addresses 1-8.

If you program it with any turnout address from 9-16 (say 10) , then the decoder will be set to operate addresses 9-16.

And so on. 

I hope you found this quick tutorial helpful.