Choosing a digital command station

Benjamin | TrackDrawer.com · published 12 November 2026

You choose a digital command station first by protocol: it has to speak the language of the decoders in your locos. After that you look at the current it delivers (in amps), at how you want to control your trains, and at what you want to connect later: feedback modules, boosters and a computer. A command station with enough current for your first few years and a good path to expansion is usually a better buy than the biggest one on the market.

What a command station does

In digital control the command station replaces the controller. It puts a constant voltage on the track and sends the commands for locos, turnouts and signals along with it. It remembers which loco is on which address, shows that on a screen or handset, and notices when a short circuit occurs somewhere. What digital control changes compared with analogue is covered in analogue or digital control.

Before you buy, ask yourself six questions. They are listed here in order of how much they weigh.

1. Does it speak your locos' language?

First check which decoders are in your locos, and which accessory decoders you have or want. A command station that speaks DCC controls most two-rail brands. If you run Märklin three-rail, you need a command station that speaks Motorola and mfx; if it also speaks DCC, you can add locos with a DCC decoder. A command station that runs several protocols side by side is the safest choice for a mixed fleet.

The protocols themselves, and what each one can do, are covered in DCC and Märklin Motorola. Do not go by the brand alone: what a command station supports exactly is in its manual.

2. How much current does it deliver?

The current in amps tells you how many locos, lit coaches and other loads the command station can supply at once. If more is running than it can handle, it shuts down as if there were a short circuit. How much a single loco draws varies a lot by model, scale and load: a loco with sound, a smoke generator or a long train behind it draws more than a bare loco standing still. The manual or a measurement gives you the real figure.

For comparison, the command stations and the booster in our digital catalogue, with the current the catalogue lists:

The difference between 1.9 and 5 A is large. A small layout with one or two trains at once runs comfortably on the smallest figure; if you want five trains with lit coaches running at the same time, you need one of the bigger units or an added booster. More amps is not always better: in a short circuit more current flows before the command station trips. On a small scale such as N a heavy command station is therefore no advantage; many units let you set the trip threshold yourself.

3. How do you want to control?

There are three ways, and many command stations combine them.

• On the command station itself. A large screen shows locos, turnouts and sometimes a control panel. Handy if you can see the whole layout from one spot.
• With handsets. If you want to walk along the layout, or several people run trains at once, a connection for extra handsets matters. They hang off the command station on a bus of their own, and not every bus fits every command station.
• From a computer or app. A network or USB connection lets you drive with a program, set turnouts from a track diagram and run trains automatically.

Also check how many locos the command station stores and how easily you add a new one. With mfx a loco registers itself; with DCC you set the address and call up the loco on that address.

4. How do you connect feedback?

Feedback tells the command station where a train is. It is the basis for everything that happens on its own: a train that stops at a signal, or a fiddle yard that knows which road is free. Some command stations have a connection for a feedback bus such as s88, others need an interface module, and with others it runs through the computer. Think about how many detectors your layout will eventually have and whether the command station handles them directly or through a module. How feedback works is covered in feedback: knowing where your train is.

5. Can you add a booster?

A booster takes over the digital signal from the command station and powers a part of the layout with its own current. That way you split a large layout into several power districts. Each district is electrically separate from the others and has its own feeders. Check whether the command station has a booster connection and which boosters fit; that is usually tied to the brand.

A booster solves a shortage of current, not a voltage drop from wires that are too thin or too few feeders. The difference is explained in voltage drop on a large layout.

6. What comes later?

A few questions you ask now will save you buying a second command station later:

• Programming track. A separate output where you read and change a decoder's settings without disturbing the rest of the layout.
• Accessory decoders. Do your accessory decoders speak the same protocol as the command station? A command station that sets turnouts by address has to know how it counts those addresses.
• Updates. Command stations get software updates. One that is still maintained gets new features and fixes.
• Power supply. A command station runs from its own power supply or transformer. Check whether it is included and whether it can also power a booster or the accessory decoders.

In short

Command station and booster in TrackDrawer

With TrackDrawer's digital layer (Pro) you add your command station and boosters to your collection. The automatic assignment takes the first command station in your collection as the supply of the main district. Each booster gets a district of its own, and each district gets a terminal track as its feeder; if one is missing, the wiring diagram tells you in which district to add it. If there is no command station in your collection, it shows up under shortages. The wiring diagram and the export to Rocrail and JMRI follow from that assignment. The digital components in the catalogue are currently those for Märklin C track.

Add your command station and boosters to your collection in the app and let TrackDrawer build the power districts and the wiring diagram.