A digital tachograph is a device fitted to a vehicle that digitally records its speed and distance, together with the driver's activity selected from a choice of modes. In Europe, it succeeded the analogue

tachograph A tachograph is a device fitted to a vehicle that automatically records its speed and distance, together with the driver's activity selected from a choice of modes. The drive mode is activated automatically when the vehicle is in motion, an ...

as a result of

European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...

regulation 1360/2002 that made digital tachographs mandatory for all relevant vehicles manufactured after August 1, 2005. Digital tachographs would be required as of May 1, 2006 for all new vehicles for which EWG regulation VO(EWG)3820/85 applies, as is published in the official newsletter of the European Union L102 from April 11, 2006.

Digital tachograph system

A digital tachograph system consists of a digital driver card, the tachograph

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

, and a sender unit mounted to the vehicle

gearbox A transmission (also called a gearbox) is a mechanical device invented by Louis Renault (who founded Renault) which uses a gear set—two or more gears working together—to change the speed, direction of rotation, or torque multiplication/r ...

. The sender unit produces electronic pulses as the gearbox output shaft turns. These pulses are interpreted as speed data by the head. The sender unit and head are electronically paired and the pulses from the sender to the head are

encrypted In cryptography, encryption (more specifically, encoding) is the process of transforming information in a way that, ideally, only authorized parties can decode. This process converts the original representation of the information, known as plain ...

, therefore deterring tampering by intercepting or replicating the pulse signal in the intermediate wiring. As well as automatically receiving speed data, the tachograph records the driver's activity selected from a choice of modes. The 'drive mode' is activated automatically when the vehicle is in motion, and digital tachograph heads usually default to the 'other work' mode upon coming to rest. The 'rest' and 'availability' modes can be manually selected by the driver whilst stationary. In Europe, drivers are legally required to accurately record their activities, retain the records and produce them on demand to transport authorities who are charged with enforcing regulations governing

drivers' working hours Drivers' working hours is the commonly used term for regulations that govern the activities of the drivers of commercial goods vehicles and Passenger Carrying Vehicle, passenger carrying vehicles. In the United States, they are known as hours of ...

. Regulation (EC) 561/2006 of the

European Parliament The European Parliament (EP) is one of the two legislative bodies of the European Union and one of its seven institutions. Together with the Council of the European Union (known as the Council and informally as the Council of Ministers), it ...

and of the

Council A council is a group of people who come together to consult, deliberate, or make decisions. A council may function as a legislature, especially at a town, city or county/shire level, but most legislative bodies at the state/provincial or natio ...

defines drivers hours.

Digital tachograph head models

* VDO DTCO 1381 / VDO DTCO 2.2 / VDO DTCO 4.0-4.0e (Smart) / VDO DTCO 4.1(Smart version 2) * Stoneridge Electronics SE5000 * Actia SmarTach * Efkon Efas 3 / Intellic Efas 4

Digital card types

There are several types of

digital card The term digital card can refer to a physical item, such as a memory card on a camera, or, increasingly since 2017, to the digital content hosted as a virtual card or cloud card, as a digital virtual representation of a physical card. They shar ...

, depending on the function of the card owner: * Driver cards are used by drivers to record driving information. * Company cards are used by operators to retrieve data regarding their employees from the tachograph head. It also allows a company to lock information so that it cannot be subsequently obtained by another operator. * Control cards are used by law enforcement agencies to retrieve data from the tachograph head. A control card overrides any company locks put in place by operators. * Workshop cards are used by authorized tachograph technicians to fit and calibrate tachographs.

Data storage

The activity information is stored in the tachograph head's internal memory and simultaneously onto the

flash memory Flash memory is an Integrated circuit, electronic Non-volatile memory, non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for t ...

chip contained within the digital driver card whilst it is inserted into the head. A digital driver card is issued to an individual driver by a country's driving authority on application. In the UK this is the

DVLA The Driver and Vehicle Licensing Agency (DVLA; ) is the organisation of the Government of the United Kingdom, British government responsible for maintaining a database of drivers in Great Britain and a Vehicle register, database of vehicles f ...

. Speed information is also stored, but only on the tachograph head's internal memory. Speed data is stored in at least 1-

hertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in ter ...

intervals, depending on the model of tachograph head. When either

memory bank A memory bank is a logical unit of storage in electronics, which is hardware-dependent. In a computer, the memory bank may be determined by the memory controller along with physical organization of the hardware memory slots. In a typical synchro ...

is full, the oldest data is automatically overwritten with the current data. Design specifications prevent data being altered or deleted, therefore ensuring the integrity of the data for subsequent analysis and presentation in a court case. Data can be locked in the tachograph head by using a company card. This ensures that the data cannot be retrieved by another company should the vehicle subsequently change ownership, or in the case or lease or hire vehicles that are used by many companies during their life. All data can still be retrieved by use of a control card or a workshop card. The retrieved data should be stored as described i
European Regulation 1360/2002
in file that can be imported into tachograph analysis software. These files needs to be named properly as required by authorities in certain countries. The extensions used for the stored files are DDD, V1B or C1B in France and TGD in Spain.

Comparison with the analogue system

Advantages of digital tachographs

The digital data stored by the tachograph system can be analysed by computer and infringements automatically identified. Digital data is encrypted and cannot be altered or deleted by the driver once stored on the card or in the head. Information is more explicitly defined in digital form and is less likely to be misinterpreted. When an analogue chart is visually analysed, a margin of error is present, dependent on the quality of the recording and the skill level of the analyst.

Disadvantages of digital tachographs

Without a digital card reader, computer and analysis software, the data can be more difficult to interpret as it is not visually represented as the analogue chart is, and requires mathematical calculations to decipher the information from its presented format. Some

Renault Renault S.A., commonly referred to as Groupe Renault ( , , , also known as the Renault Group in English), is a French Multinational corporation, multinational Automotive industry, automobile manufacturer established in 1899. The company curr ...

branded tachograph heads can produce printed information in a graphical format, similar in appearance to the activity trace on an analogue tachograph chart.

Newer models of tachographs or smart tachographs (Annex 1C)

Tachograph regulation Annex 1C introduced the second generation of digital tachographs called Smart tachographs or 1C tachographs. These newer models connected with

GPS receivers A satellite navigation (satnav) device or GPS device is a device that uses satellites of the Global Positioning System (GPS) or similar global navigation satellite systems (GNSS). A satnav device can determine the user's geographic coordinates ...

, secondary speed sensors and radio communication interfaces for authorities to remotely check for possible infringements avoiding this way the unnecessary roadside checks. Position data is recorded every 3 hours of work and border crossings are also stored. Version 2 of smart tachographs also records Load and unload operations and also has the possibility to enter load types.

Data retrieval

All digital tachographs can be downloaded through their front connector with a specialized device. Newer models also provide a remote download interface on their C connector. Installing the remote download units requires a workshop and many countries require the tachograph to be calibrated after installation. Mostly all manufacturers of download devices can deliver manual or front connector download devices or completely automated tachograph download systems.

Manual download systems

VDO DLK PRO DOWNLOAD KEYVDO SmartTerminalTacho2SAFE with free TachoSAFE Lite analysis softwareTacho5SAFE with online analysis on TachoSAFE WEBOptac DownloadTOOL by Stoneridge
Note: All of the above systems are smart and smart 2(Annex 1C) ready.

Fleet management or automatic download systems

TIS WEB
- provides full fleet management
TachoSAFE WEB
- basic fleet management and completely automated downloads
Optac3
- tachograph analysis software
Tachogram
- tachograph download and analysis tool

References

{{Authority control European Union transport law Vehicle law de:Tachograph#Digitaler Tachograph