Software
Trying it without a layout
You don't have any devices yet, or your layout isn't built? In the dry run you build and drive your layout without power. It isn't a cut-down preview but the same layout – only the devices are virtual.
The dry run isn't a cut-down preview but the same layout without power. The same program is in charge, the same automation calculates, the same routes are set and locked – only the devices are virtual. What gets made up is the occupancy report, the RailCom number, the turnout position and the state of the track power. Anything else your layout is missing for a test run is filled in by the simplified simulation itself (see “Simplified or exact”).
Switching in and out
The “Sim” button in the header switches over. Only administrators can see it. Afterwards, “Dry run” appears on the right and all devices report as online. If the header shows “BOOSTER OFF”, click it to switch the track power on – you switch it on and off with the booster switch as usual.
A second click on “Sim” loads the real layout again. The hardware stays disconnected; you switch it online yourself.
What happens to your real layout
- The track plan is shared. What you draw in the dry run stays – provided the layout is a project folder (see below).
- The operating state is kept separate. Trains, turnout positions and the log from the dry run are gone the next time you switch in; practice always starts from the real state.
- What has been learned is only read. Speed curves and calibrations are not overwritten.
- The log fills up as normal in the dry run (Log and diagnostics).
Simplified or exact
The simulation comes in two strengths. The default is the simplified one – for new and existing layouts. An administrator can switch it under “System” › “Track plan” in the “Program start” card with the “Exact simulation” tick box, and only while no simulation is running.
| Simulation | Simplified (default) | Exact |
|---|---|---|
| What for | Checks the operation, not the wiring. Tracks and blocks are enough. | For reproducing faults and checking your settings before the real layout runs. |
| What is missing in the plan | Makes it up (list below). None of it ends up in your layout file. | Makes up nothing. What is missing in the plan is also missing in the dry run and is listed in “🔎 Check track plan”. |
| Locos | Every loco runs on a fixed, straight speed curve. Calibration and learning are paused, and RailCom doesn't turn any train round. | As on the layout. |
The simplified simulation adds:
- a virtual command station and a virtual feedback module if the project has none,
- a virtual feedback sensor covering the full block length for every block without a feedback address,
- a borrowed address for every turnout and every signal without an address – a turnout with two motors gets two,
- a booster if the plan has none.
A device that was switched off before you switched in stays off; its feedback sensors are handled by the virtual feedback module.
The steps in the dry run
The dry run is the path with a layout, minus the “Connecting devices” step. Everything else is the same:
- Install, sign in, create a layoutThe first three steps: Installing and starting, Signing in and licences, Creating a layout.
- Dry run on“Sim” in the header.
- Track planDraw the oval, insulated joints, blocks and feedback sensors as in Your first track plan – in the exact simulation with addresses (see below).
- TurnoutsAs in Placing and connecting turnouts – in the exact simulation with addresses.
- Train class, loco and trainAs in Adding a loco and driving, placed from the depot.
- First runAs described there – here you can be a bit bolder straight away.
What may surprise you in the exact simulation
In the simplified simulation, LoDi-Aura takes care of both for you. In the exact one:
- Feedback sensors need addresses – even though no feedback device is connected. The virtual layout builds its picture from your track plan, and feedback sensors without an address in the form module.channel don't belong to any block; they simply don't exist. Likewise, the feedback sensor lengths only count if every sensor has a length and the total matches the block length. Otherwise the block counts as a single piece, and the train is only ever “somewhere in it”.
- Turnouts need addresses – unlike with real hardware. In the virtual world, a turnout without an address is unknown and can therefore be passed in any position: the train runs through a wrongly set turnout without complaint. If you want to practise how routes set turnouts, give every turnout an address.
What the dry run can do – and what it can't
| Works as on the layout | Doesn't work |
|---|---|
| Drawing, blocks, feedback sensors, turnouts | Current measurement and short circuits – without booster modules in the track plan there is nothing to measure |
| Placing and driving trains, all three driving modes | Anything a real device has to answer: reading firmware, bus scan, reading and writing CVs, reading in a loco |
| Setting, booking and locking routes; block protection, collision guard, trains passing | Real currents in the feedback monitor – it only shows the virtual feedback sensors |
| Sequences in full – the sequence control runs even without a single train, and the level crossing visibly switches | |
| Stations, shunting, zigzag runs |
The “Set online” and “Set offline” buttons on the device cards change nothing in the dry run: all devices are virtual and always there – even if the message afterwards says “… is online”. On the device page, “Capabilities & Usage” and the device settings below it are locked, with the note “Dry run: the simulation works with its own devices. Settings here do not apply and are not saved — change them after leaving the simulation.”