What .ddd files are: driver card and vehicle unit
A digital tachograph stores data in two places. The driver card holds the activity of the person who inserted it. The vehicle unit (VU) is the tachograph inside the cab and holds what was recorded on that vehicle, whoever drove it.
Data taken from either source is saved as a .ddd file. So there are two kinds of files: driver card files, one per driver, and vehicle unit files, one per truck. A company needs both, because each shows things the other does not.
Why the company must download
The duty sits with the transport undertaking, not only with the driver. Under Regulation (EC) No 561/2006, Art. 10(5)(a), the undertaking must ensure that all data are downloaded from the vehicle unit and the driver card as regularly as the Member State stipulates, and more often where needed so that all data on activities for the undertaking are downloaded.
If your company operates under Moldovan rules, or under the AETR for international transport outside the EU area, check the exact download obligations with the competent national authority and the official AETR text published by UNECE. The intervals below come from EU law.
Maximum intervals: 28 days for the card, 90 days for the VU
Commission Regulation (EU) No 581/2010, Art. 1(3) sets the longest allowed gap between downloads of relevant data: 90 days for the vehicle unit and 28 days for the driver card. "Relevant data" means everything the digital tachograph records except detailed speed data.
Two details matter in practice. First, according to recital 3, only days with a recorded activity count towards these periods, so a card that sat in a drawer during leave does not use up its 28 days. Second, Art. 1(4) requires the download to be made so that no data is lost. A download that comes too late, after older data was overwritten, does not meet that.
These are maximums. Regulation 561/2006 also says to download more frequently where needed, and in practice many fleets schedule downloads well inside the limits so that a missed slot can still be repaired.
Keeping the files: 12 months and access for inspectors
Under Art. 10(5)(a) of Regulation 561/2006, all downloaded data from both vehicle units and driver cards must be kept for at least 12 months following recording. If an inspecting officer requests it, the data must be accessible, directly or remotely, from the undertaking's premises.
Regulation (EU) No 165/2014, Art. 33(2) adds that undertakings keep record sheets, printouts and downloaded data, and give copies of data downloaded from driver cards to the drivers concerned who request them. A searchable archive per driver and per vehicle makes both duties simple.
The 56-day roadside rule concerns the driver
From 31 December 2024, Art. 36 of Regulation 165/2014, as amended by Regulation (EU) 2020/1054, requires a driver at a roadside check to be able to produce the records for the current day and the preceding 56 days. Before, the period was 28 days. The records are the driver card, manual records and printouts.
This is a rule about what the driver can show to the inspector, not a new download interval for the company. It does not replace the 28-day and 90-day limits above. It does mean that the data the driver carries and the data the office archives should agree, which is one more reason to download regularly.
Manual download vs remote download
Manual download means someone connects a download device or card reader to the tachograph or reads the driver card, then saves and sorts the files. It works, but it depends on the truck being available and on someone remembering the deadline. Remote download moves the files from the tachograph over the mobile network, without a visit.
| Manual download | Remote download | |
|---|---|---|
| Visit to the vehicle | Needed each time | Not needed |
| Driver card | Read with a card reader, with the driver present or the card handed over | Downloaded from the tachograph over the mobile network |
| Company card | Used at the vehicle for the VU | Stays in the office in a reader |
| Deadlines | Tracked by hand | Office sees what is done and what is due |
| Archive | Files saved and sorted by hand | Files stored per driver and per vehicle |
| Risk of a missed period | Higher, depends on people and logistics | Lower, downloads run without a visit |
What remote download needs
Driver card and vehicle unit files can both be downloaded this way. VU downloads must be authenticated with the company card, which is why the reader has to stay online.
- A Teltonika FMB640, FMC650 or FMM650 tracker connected to the digital tachograph. See the compatible devices.
- The company card for authenticating vehicle unit downloads. It stays in the office in a standard card reader.
- A Windows 10 or 11 PC in the office running Tafi Card Authenticator, a free app that makes the card reachable. The card can be used only while the app is running.
- A mobile data connection on the tracker, since the .ddd files travel over the mobile network.
How Tafi GPS does remote download
Tafi GPS downloads driver card and vehicle unit .ddd files over the mobile network from trucks with an FMB640, FMC650 or FMM650, with no workshop visit. The company card stays in the office. Tafi Card Authenticator is a free Windows 10/11 app for standard CCID card readers; it starts with Windows, shows the card number, company and validity, and reports to Tafi GPS so the office can see whether it is online.
Files are archived per driver and per vehicle. The office sees which downloads are done and which are due, and can download the original .ddd files as one archive per vehicle or card and period. Details are on the tachograph page and in GPS for trucks.
Tafi GPS also checks downloaded activity against Regulation (EC) No 561/2006 (daily and weekly driving, breaks, daily and weekly rest) and lets you confirm or dismiss each finding. It does not model AETR-specific rules and does not replace your company's own legal responsibility.
Want to see it? Start the free 7-day demo or contact us, and we will check whether your trucks and tachographs fit.