How to choose a DCC command station
Work out what you need from a DCC system – power, programming, expansion, computer connection and throttles – so you buy one that fits your layout now and later.
- Time
- 30 minutes
- Difficulty
- Easy
- Cost
- Higher cost
- Steps
- 7
- Checked
What you’ll need
- A rough plan of your layout and the number of locos you expect to run at once
- A list of your locos and whether they have decoders or sockets
Before you start
- Use the power supply recommended by the system maker. ESU advises fusing any supply and using transformers designed for model railways.
Step by step
-
Step 1: Estimate how much power you need
Add up how many locos will run at the same time. Digitrax, for example, says a 5 A booster typically runs 10–15 average N-scale locos or 6–10 HO locos (DCS240 manual). Sound locos, lit coaches and larger scales need more. You can always add a booster later, so think about expansion rather than buying the biggest box.
Next: step 2 -
Step 2: Check programming features
You will want a programming track output that can read back CVs (service mode) and support for programming on the main (POM) so you can adjust a loco while it runs. Some systems give the programming track its own terminals so the layout keeps running while you program (the Digitrax DCS240 does this); others switch one output between modes.
Next: step 3 -
Step 3: Look at expansion
Ask: can I add boosters and power districts? Is there a bus for accessory and detection modules (for example Digitrax LocoNet, Lenz XpressNet, MERG CBUS or NMRA LCC)? Can I add more handsets?
Next: step 4 -
Step 4: Decide how you'll drive
Options include tethered or wireless handsets, phone apps (WiThrottle-protocol apps such as Engine Driver on Android and WiThrottle on iOS), and computer software. If you plan automation, make sure the system has a computer interface that your chosen software supports – check JMRI's supported hardware list and the iTrain or Rocrail system lists.
Next: step 5 -
Step 5: Consider an open-source option
DCC-EX is free, open-source command station software (GPL v3) that runs on an Arduino Mega or ESP32 with a motor driver board, available DIY or ready-to-run. It works with JMRI, Rocrail, Engine Driver and WiThrottle and has its own automation language, EXRAIL. It suits people happy with a bit of tinkering.
Next: step 6 -
Step 6: Check scale and voltage
Make sure the track voltage suits your scale. The NMRA gives a nominal 12 V for N and smaller, 15 V for HO/OO to O, and 18 V for large scale (S-9.1 draft). Many systems let you choose; DCC-EX warns that too high a voltage can damage locos.
Next: step 7 -
Step 7: Make a shortlist and read the manuals
Download the manuals of two or three systems before buying. Look for: current rating, programming track, booster support, computer interface, RailCom support if you want loco identification, and how accessory decoders are addressed.
Tips
- If you will automate with a computer, choose the software first, then a command station it supports well.
- Buy from a UK model shop that can help with setup; the manufacturer's manual is the real specification.
Questions people ask
Is a bigger amp rating always better?
Not necessarily. Very high current into small-scale track can damage wheels or wiring in a short. Districts with their own boosters and sensible trip settings are safer.
Can I mix brands?
Basic loco control follows NMRA standards, so decoders from any maker work with any compliant system. Control buses (LocoNet, XpressNet etc.) are brand-specific, so handsets and boosters are usually best kept to one system.
What is RailCom?
A way for decoders to send information back, such as their address, during a short cutout in the DCC signal (NMRA S-9.3.2). Both the command station/booster and the decoder must support it.
Sources
Checked 18 October 2026. We wrote this guide in our own words, using:
- Digitrax DCS240 command station manual (digitrax.com)
- NMRA S-9.1 Electrical Standards for DCC (draft revision, June 2026) (nmra.org)
- DCC-EX home (dcc-ex.com)
- DCC-EX CommandStation-EX licence (GPL v3) (github.com)
- JMRI supported hardware (jmri.org)
- iTrain: supported digital systems (berros.eu)
- Rocrail wiki home (rocrail-wiki.net)
- NMRA S-9.3.2 Bi-Directional Communication (RailCom), draft (nmra.org)
- ESU LokPilot 5 instruction manual, Edition 7 (distributor copy) (intermountain-railway.com)
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Printed from dcctrainautomation.uk/guides/choose-a-dcc-command-station/ · Checked 18 October 2026 · General information only. Follow the maker’s instructions for your own equipment, and keep mains wiring inside properly made, enclosed power supplies.