The DDD file is the primary data source for the digital tachograph, yet it remains notoriously difficult to interpret without specialized software. Because the data is stored in a compressed binary format, simply opening it with a text editor will yield unreadable symbols.
In this guide, we provide a forensic-level walkthrough on how to open, decode, and interpret the critical blocks of information hidden within your tachograph records.
Phase 1: Decoding the Binary Format
Before reading the data, you must understand that .ddd files are encrypted to prevent tampering. They contain raw hexadecimal values that represent specific activity codes.
- The Challenge: Standard office programs (Excel, Word) cannot verify the digital signature embedded in the file.
- The Solution: Use an online parser like TachoTools. Our engine acts as a translator, turning binary strings into human-readable timestamps in UTC time.
Phase 2: Identifying Key Information Blocks
Once decoded, a professional reading of a DDD file follows these six critical steps:
1. Verification of Card & VU Data
Identify the file source. Does it come from a Driver Card (.C1B) or the Vehicle Unit (.V1B)? Verify the cardholder's name and the vehicle's VRN (Registration Number).
2. Analysis of Activity Codes
Distinguish between the four main modes: Driving (Wheel icon), Rest (Bed icon), Availability (Box icon), and Other Work (Hammer icon).
3. Calculating Driving Limits
Cross-reference timestamps to calculate 4.5h driving blocks. Check for daily driving exceedance and weekly limits.
4. Checking Rest Compliance
Audit 9-hour and 11-hour daily rest periods. Ensure the weekly rest cycle hasn't been interrupted illegally.
Phase 3: Interpreting Technical Events
A deeper reading reveals "Events and Faults." This section is where transport inspectors look for evidence of tachograph manipulation. You must check for:
- Power Supply Interruptions: Potential signs of battery disconnection.
- Motion Sensor Faults: Errors in the speed signal transmission.
- Card Conflicts: Periods where a driver was driving without a card inserted.
Phase 4: Converting Data for Official Use
Analyzing raw data is tedious. For internal audits or labor disputes, it is often necessary to:
By converting to PDF, you get a clean visualization of the velocity graph and activity timelines, which are much easier to present in legal proceedings.
Transform Raw Data into Compliance Reports
Don't risk manual interpretation. TachoTools automatically decodes your files and highlights every potential infringement for you.
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