Digital tachograph files are legally binding electronic documents that record the activities of heavy vehicles and their drivers. These files are more than just text documents; they are complex data containers protected by a digital signature that guarantees information integrity and prevents tampering.
Managing these digital assets correctly is the cornerstone of avoiding serious infringements. Moreover, ensuring a compliant allowance calculation requires auditable and truthful records, shielding your company during labor audits or Department of Transport inspections.
File Types and International Standards
While European regulations unify the core criteria, file extensions often vary depending on the country of origin or the specific download software manufacturer:
Driver Card Files (.C1B / .TGD)
These contain driver activity (driving, rest, other work) for the last 28 days (extending to 56 days in newer Gen2 models). The .TGD format is the standard across several EU regions.
Vehicle Unit Files (.V1B / .DDD)
Records data from the Vehicle Unit (VU), including overspeeding incidents, system failures, manipulation attempts, and motion sensor technical data.
Download Protocol and Chain of Custody
Regulations demand rigorous proactivity. Failure to meet download deadlines can result in heavy sanctions for each missing period:
- Driver Card: Must be downloaded at least every 28 calendar days.
- Vehicle Unit: Must be downloaded at least every 90 calendar days.
- Legal Archiving: Files must be kept in their original encrypted format for at least 365 days, ensuring immediate availability for authorities.
For complex organizations, multi-company management is vital to maintain file traceability when a driver provides services across different branches or different vehicles within the fleet.
How to Interpret Encrypted .DDD Files?
Due to their technical nature, a .DDD file cannot be read with a conventional text editor. It requires specialized software that verifies the digital signature public key. Learning how to open tachograph files is crucial for performing internal audits.
When using TachoTools, our system processes these metadata blocks and generates a visual compliance dashboard. This allows traffic managers to verify at a glance if the file signature is valid and identify any data gaps that need justification.
Data Security (GDPR Compliance)
Tachograph files contain highly sensitive personal data. Storage must comply with the General Data Protection Regulation (GDPR). TachoTools guarantees that your .DDD file custody is performed on high-security encrypted servers with restricted access.
Technical Resources & Manuals
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