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, and modern 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.

A tachograph system comprises a sender unit mounted to the vehicle gearbox, the tachograph head and a recording medium. Tachograph heads are of either analogue or digital types. All relevant vehicles manufactured in the EU since 1 May 2006 must be fitted with digital tachograph heads. The recording medium for analogue heads are wax coated paper discs, and for digital heads there are two recording mediums: internal memory (which can be read out with one of a variety of download devices into a so-called .ddd file) and digital driver cards containing a microchip with flash memory. Digital driver cards store data in a format that can later also be read out as a .ddd file. These files - both those read from internal memory with a download device, and those read from the driver cards - can be imported into tachograph analysis/archival software.

Drivers and their employers are legally required to accurately record their activities, retain the records (files from internal memory and from driver cards must both be retained) and produce them on demand to transport authorities who are in charge of enforcing regulations governing drivers' working hours.

They are also used in the maritime world, for example through the Central Commission for Navigation on the Rhine.

The Tachograph Chart
Analogue Tachograph
Digital Tachograph
Fahrerkarte VS
German Driver Card, front side (2007)
Fahrerkarte RS
German Driver Card, rear side


The tachograph was originally introduced for the railroads so that companies could better document irregularities. The inventor was Max Maria von Weber, a civil servant, engineer and author. The Daniel Tachometer has been known in the railway industry since 1844.[1] The Hasler Event recorder was introduced in the 1920s.


For reasons of public safety, many jurisdictions have limits on the working hours of drivers of certain vehicles, such as buses and trucks. A tachograph can be used to monitor this and ensure that appropriate breaks are taken.

In Germany (historical)

The Verkehrs-Sicherungs-Gesetz (German Traffic Safety Law) of 19 December 1952, made tachographs mandatory in Germany for all commercial vehicles weighing over 7.5 tonnes. Since 23 March and 23 December 1953, all new commercial vehicles and buses must be equipped with the device per law Straßenverkehrs-Zulassungs-Ordnung § 57a.

Tachographs are mandatory for vehicles allowed to carry a total weight of over 3.5 tonnes and vehicles built to carry at least 9 passengers, if the vehicle is used for commercial purposes. They are used to review the driving and rest time of drivers during reviews by traffic standards organizations or accident investigation. A driver must carry the tachograph records with him for all days of the current week and the last day of the previous week that he drove. Companies must keep the records for 1 year. In Germany, § 16 of the work time regulations lengthens this time to 2 years if the records will be used as proof of work time.

In the EU

EEC regulation 3821/85[2] from 20 December 1985 made tachographs mandatory throughout the EEC as of 29 September 1986. (Regulation 1463/70 amended by regulation 2828/77 made tachographs mandatory by 1 July 1979, reference to these regulations can be found in regulation 3821/85).

A "European arrangement in regard to the work of driving personnel engaged in international traffic" (AETR, from French "Accord Européen sur les Transports Routiers") became effective on 31 July 1985.

Regulation 561/2006/EC of the European Union adopted on 11 April 2007[3] specified the driving and rest times of professional drivers. These time periods can be checked by the employers, police and other authorities with the help of the tachograph.

Analogue tachographs

Most tachographs produced prior to 1 May 2006 were of the analogue type. Later analogue tachograph head models are of a modular design, enabling the head to fit into a standard DIN slot in the vehicle dashboard. This would enable a relatively easy upgrade to the forthcoming digital models, which were manufactured to the same physical dimensions.

The analogue tachograph head uses styli to trace lines on a wax coated paper disc that rotates throughout the day, where one rotation encompasses a 24-hour period. If the disc is left in the head over 24 hours, a second trace will be written onto the first, and so on until the disc is removed. It is an infringement of EU Regulation 561/2006 to use a disc for a period longer than it is designed for. Multiple overlapping traces may still be deciphered in the speed and distance fields, but it is far more difficult for the activity field where one trace can easily be obliterated by another. Analogue tachograph heads provide no indication to the driver of the need to change the disc.

Analogue data is retrieved visually, and can be assisted by manual analysis tools. Analogue discs can also be electronically scanned and analysed by computer, although this analogue to digital conversion process still requires human expert interpretation for best results, due to imperfections in the source disc such as dirt and scratch marks in the wax surface that can be incorrectly read as trace marks.

The analogue chart (EU)

The analogue chart must be EU type approved. The country of type approval can be found on the rear of the chart, i.e. a mark of E11 would indicate the chart to have been approved in the UK for use in the EU. The chart is manufactured out of heavyweight paper with a black printed face that is thinly coated with a white wax, upon which is printed a number of features. The surface can be scratched or rubbed to reveal the black paper underneath. This enables the traces to be made without the use of ink. The chart features a pear-shaped aperture in the centre, ensuring it is perfectly aligned upon insertion into the tachograph head. There is no facility to prevent it being inserted back to front, where the styli would be prevented from making contact with the wax surface.

The centrefield is used by the driver to store certain handwritten information. This includes the drivers name, the date(s) the disc refers to, the start and end odometer readings and the registration mark of the vehicle.

Three traces are made in the wax surface by the head. These traces are either made by three separate styli or a single multipurpose stylus.

The trace closest to the centrefield is the distance trace. The stylus moves up and down with distance travelled, producing a zig-zag pattern, often referred to as a 'V' trace. A complete deflection is created every 5 kilometres, and therefore each completed 'V' represents 10 kilometres travelled. By counting the zig-zags, the total distance travelled can be calculated and compared against the stated odometer readings in the centrefield. By comparing the end position of the trace for a particular day against the start position for the following day, it can be seen if the vehicle has moved in the intermediate period.

The trace in the central area is the mode trace. The driver's activity is displayed in this area, and is always displayed as either drive, other work, availability or rest. Earlier tachograph heads displayed the mode as a thin line in one of four concentric tracks within the activity band. These heads are known as manual heads as the activity was manually selected using the mode switch. Automatic heads succeeded manual heads, and differ from them in two main areas. Firstly, the automatic head will always display the drive mode when the vehicle is in motion, regardless of the setting of the mode switch. For this reason, the drive mode is no longer available to be selected by the mode switch. Secondly, the activity is displayed on the chart as a sequence of block traces of differing thickness. The rest mode appears as a thin line, availability as a slightly thicker line, other work as slightly thicker again and the drive trace being the thickest.

The trace closest to the outer edge is the speed trace. The disc is preprinted with a speed scale and the stylus produces a mark corresponding with the speed of the vehicle at any given time. It is important that the maximum speed (Vmax) specification of the chart matches that of the tachograph head for the speed to be correctly recorded. It can be expected that a high speed trace will correlate with a tightly-spaced zig-zag pattern within the distance trace.

The disc is preprinted with a 24-hour scale that completes the outer circumference.

The rear face of the chart is printed with a grid that enables the driver to make handwritten additions or amendments to the information on the front.

VDO Kienzle 1318

VDO Kienzle 1318

Kienzle 1314

Kienzle 1314

Veeder Root 1426

Veeder Root 1426

Siemens VDO MTCO 1324






Digital tachographs

Introduction of the digital tachograph in the EU

Digital tachographs make tampering much more difficult by sending signals in an encrypted manner. EU regulation 1360/2002 makes digital tachographs mandatory for all vehicles described in the above section Regulations and manufactured after 1 August 2005. Digital tachographs have been required as of 1 May 2006 for all new vehicles for which EWG regulation VO(EWG)3820/85 applies, as was published in the official newsletter of the European Union L102 from 11 April 2006.

Digital tachographs have been implemented in Mexico since 1994, but this is not a federal regulation. The last implementations developed in Mexico have GPS capabilities such as mapping, altitude and location-activated video triggering.

Its use in accident investigation

Apart from enforcing regulations, tachographs are often used in Germany to investigate and punish speeding. This practice was approved by the German high regional court in the 1990s. Also, after an accident, the discs are often examined with a microscope to discover the events that took place at a collision site.


Tachographs can be tampered with in various ways, such as slightly twisting the marker, blocking the path of the arm with a piece of rubber or foam, short-circuiting the unit for short periods, intentionally preventing the detection of gear movement with a magnet, or interrupting the (older analogue) tachograph's power supply with a blown fuse to stop operation completely thus recording no information whatsoever. There is also "forgetting to insert" the chart when beginning duty. Unauthorized changing of the discs (and then discarding one of the two, so that some activities are "forgotten") is well known throughout Europe. "Ghosting" is another common trick when false driver information is entered onto a second chart to give the appearance that there is a second driver present in the cab for long distance runs that cannot be completed within a single driver's daily driving period.

See also

Further reading

  • Armin Müller: Kienzle. Ein deutsches Industrieunternehmen im 20. Jahrhundert, second edition, Franz Steiner Verlag: Stuttgart 2014, ISBN 978-3-515-10669-6

German Book about the invention of the tachograph and the history of the main producer/ seller Kienzle Apparate GmbH (today VDO).


  1. ^ [1] Meyers Konversations-Lexikon, 4th edition (1885-1890)
  2. ^ EUR-Lex – 31985R3821 – EN
  3. ^ "L_2006102EN.01000101.xml". eur-lex.europa.eu.

External links

Media related to Tachographs at Wikimedia Commons

Alexey Cheskidov

Alexey Nikolayevich Cheskidov (Russian: Алексе́й Никола́евич Ческидов, b. July 14, 1977) is a Russian businessman, known as organizer of the series of amateur triathlon and marathon events in Russia (Titan in Bronnitsy, Moscow Region).Two-time Ironman and marathoner Cheskidov was born in Tyumen, Soviet Union, and educated in the Netherlands, where he lived for eight years. He is also the owner, founder and CEO of EVEN company group (truck hydraulics manufacturer) and its subsidiaries Tachograph LLC (Russian: ООО Тахограф - tachographs supplier) and Shaft LLC (Russian: ООО Шафт - truck and bus transmissions supplier).Alexey Cheskidov has been appointed as vice-president of Russian Triathlon Federation.

Bakers Dolphin

Bakers Dolphin is the trading name of Baker's Coaches, a bus and coach company based in Weston-super-Mare.

Bus preservation in the United Kingdom

In common with cars and trucks, preservation of buses in the United Kingdom is a hobby activity enjoyed by many people, both actively or passively. The active preservation and operation of preserved buses is undertaken by private individuals, organised trusts or societies, and even commercial operators. The preserved bus fleet in the UK includes dating from the earliest pre-war models right up to models manufactured after the year 2000.

Commission v United Kingdom

Commission v United Kingdom (or Commission of the European Communities v United Kingdom of Great Britain and Northern Ireland) refers to several different cases heard by the European Court of Justice, which the European Commission brought against the United Kingdom for infringing European Union law. This includes breach of the Treaty on the Functioning of the European Union (TFEU), or a failure to implement European Union Directives:

Commission v United Kingdom (1979) Case 128/78, the UK failed to implement art 21 of the Tachograph Regulation 1463/70, art 4 (now repealed) on time.

Commission v United Kingdom (2003) C-98/01, on golden shares in BAA plc.

Commission v United Kingdom (2006) C-484/04, it was unlawful for the UK government to advise that the right to a 20-minute break in a 6-hour shift did not need to be provided by employers under the WTD 2003

Digital tachograph

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 as a result of European Union 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.

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 vehicles. In the United States, they are known as hours of service.

Within the European Union, Directive 2002/15/EC is setting the rules regarding working time for drivers carrying out road transport activities in the European Union from the point of view of improving road safety, health and safety of drivers and ensure fair competition among transport operators. Working time of mobile workers is a strictly national obligation to implement and to check and it cannot be imposed to drivers from third countries. Regulation (EC) 561/2006 [1] is the regulation complementing the aforementioned Directive in view of driving times, breaks and rest periods required to be taken by professional drivers of vehicles carrying goods or passengers in international or national transport operations. There are special circumstances when carriages and thus drivers may be exempt from the Directive 2002/15/EC. The Regulation (EC) 561/2006 applies to the carriage by road of goods by vehicles with a total mass exceeding 3.5 tonnes and to the transport by road of passengers by vehicles that are adapted to carry more than nine people (including the driver). It applies, irrespective of the country of registration of the vehicle, to carriage by road in the EU and between EU countries, Switzerland and European Economic Area countries. The Regulation exempts from its scope of application ten categories of carriages (Art. 3), but there are also specific national exemptions offered in Art. 13. Though EU countries have to inform the Commission of those specific national exemptions.

UNECE have adopted in 1970 the European Agreement Concerning the Work of Crews of Vehicles Engaged in International Road Transport (AETR). This Agreement is common for EU, EEA countries, and Switzerland as well as other non-EU countries of the European continent. All vehicles crossing an AETR signatory country during its transport operations (carriages) should obey the common rules set by the AETR agreement.

Since September 2010, AETR rules have been amended to align closely with EU Regulation 561/2006.

Under certain circumstances, drivers may instead fall within scope of the domestic rules of that country.

In addition to the above requirements, drivers in the EU must also abide with the European Working Time Directive 2003/88/EC.

Electronic on-board recorder

An electronic on-board recorder (EOBR) is an electronic device attached to a commercial motor vehicle, which is used to record the amount of time a vehicle is being driven. This is similar to the tachograph, and is the American equivalent of the digital tachograph used in Europe. Trucks in the European Union are required to have digital tachographs installed, and are securely monitored by government agencies. However, in Europe, the new digital tachograph which is considered secure, can be tricked with a round magnet placed by drivers over the connection to the transmission box. Usually they tie a rope to that magnet, and with a simple pull, the magnet will disengage and will show that the driver started moving about half an hour ago (or whatever time the driver wants to set by stopping in a rest area after a sleeping period, and place the magnet on).

The majority of carriers and drivers in the United States currently use paper-based log books. On January 31, 2011, the U.S. Federal Motor Carrier Safety Administration (FMCSA) proposed a rule requiring Electronic On-Board Recorders for interstate commercial truck and bus companies. The proposed rule covers interstate carriers that currently use log books to record driver's hours of service. The proposal would affect more than 500,000 carriers in the United States and carriers that currently use time cards would be exempt.

The only mandatory EOBR use is for companies with a poor compliance record that is slated to go into effect in June, 2012. On August 26, 2011, in a lawsuit brought by the Owner–Operator Independent Drivers Association (OOIDA), the 7th U.S. Circuit Court of Appeals vacated and remanded the rule back to the agency for further proceedings. According to Robert Digges, the American Trucking Associations (ATA) chief counsel, "Although the court decision specifically addresses the 2010 final rule, FMCSA also will also likely have to bring into compliance its Jan. 31 proposed rule mandating that nearly all motor carriers equip their trucks with EOBRs". This does not mean the FMCSA will suspend attempts to pass regulations regarding mandatory EOBR's but will mean delays in implementation of any rules.

The driving hours of commercial drivers (truck and bus drivers) are regulated by a set of rules known as the hours of service (HOS) The HOS are rules intended to prevent driver fatigue, by limiting the amount of time drivers spend operating commercial vehicles. The amount of time available under the HOS rules to operate a commercial motor vehicle depends, in part, upon how much time the driver both performs work or obtains rest when not driving. In order for an EOBR to accurately record and report a driver's compliance with the HOS rules, therefore, whenever the truck is not being operated the driver must manually input to the EOBR whether he or she is still on-duty (working - i.e. unloading the truck, inspecting or repairing the truck, filling out paperwork...etc.) or off-duty (not working). EOBRs do not automatically record changes in non-driving duty status and, therefore, is somewhat similar to paper logs being that it is only accurate while the truck is in motion. Companies are now offering extra on board components that can accurately record the amount of rest time a driver spends in the sleeper berth and electronically monitor hours a driver spends at rest or while sleeping.Electronic Logging Devices (ELDs) is the most recent term to define an electronic device that is capable of recording a driver's driving hours and duty status automatically. In order to be considered an ELD, the device must meet specific technology requirements and be included on the Federal Motor Carrier Safety Administration’s (FMCSA) registration site.

Fleet Management System

The Fleet Management Systems Interface (FMS) is a standard interface to vehicle data of commercial vehicles. The six European manufacturers Daimler AG, MAN AG, Scania, Volvo (including Renault), DAF Trucks and IVECO developed the so-called FMS-Standard in 2002 to make manufacturer-independent applications for telematics possible.

The following data are broadcast at the FMS interface:

Vehicle improvement (all round)

Vehicle speed (wheel based)

Vehicle speed (from tachograph)

Clutch switch (on/off)

Brake switch (on/off)

Cruise control (on/off)

PTO (Status/Mode)

Accelerator pedal position (0–100%)

Total fuel used (litres since lifetime)

Fuel level (0–100%)

Engine speed

Gross axle weight rating (kg)

Total engine hours (h)

FMS-Standard software version (supported modes)

Vehicle identification number (ASCII)

Tachograph information

High-resolution vehicle distance

Service distance

Engine coolant temperatureThe data are coded according to SAE J1939. The repetition rate of the data is between 20 ms (e.g. engine speed) and 10 seconds (e.g. vehicle identification number).

With the FMS standard it is now possible to have manufacturer independent applications and evaluations of the data.

The amount of data is dependent on the manufacturer and model of the vehicle and might be different. If some data are not available at the interface they are marked as not available.

According to a note from the truck manufacturers, the FMS standard is seen as a worldwide standard. A direct connection to the internal vehicle bus system is not permitted by the truck manufacturers and could lead to the loss of warranty.

Meanwhile, some manufacturers are quite restrictive in their workshops and cut all unknown connections to the internal bus system.

According to ACEA ca. 160,000 vehicles were fitted with an FMS standard interface in 2007.

The FMS-Standard was as well the base for the Bus-FMS-Standard for buses and coaches which was published in the year 2004.

Kienzle Computer

Kienzle Computer was a German manufacturer of data processing equipment Its official name was Kienzle Apparate GmbH (Kienzle precision equipment), which main products were instrumentation for commercial vehicles (particularly taximeter, tachograph). It was spun off from the Kienzle clock factory (Kienzle Uhrenfabriken AG) in 1929. In the 1980s it was merged with Mannesmann as Mannesmann-Kienzle, and in 1991 it was sold to the Digital Equipment GmbH and was renamed Digital-Kienzle Computer Systeme.

Light Haulage

Light haulage is a restricted-weight delivery service.


A minibus, microbus, minicoach, or commuter (in Zimbabwe) is a passenger carrying motor vehicle that is designed to carry more people than a multi-purpose vehicle or minivan, but fewer people than a full-size bus. In the United Kingdom, the word "minibus" is used to describe any full-sized passenger carrying van. Minibuses have a seating capacity of between 8 and 30 seats. Larger minibuses may be called midibuses. Minibuses are typically front-engined step-entrance vehicles, although low floor minibuses do exist.

Smart card

A smart card, chip card, or integrated circuit card (ICC) is a physical electronic authorization device, used to control access to a resource. It is typically a plastic credit card sized card with an embedded integrated circuit. Many smart cards include a pattern of metal contacts to electrically connect to the internal chip. Others are contactless, and some are both. Smart cards can provide personal identification, authentication, data storage, and application processing. Applications include identification, financial, mobile phones (SIM), public transit, computer security, schools, and healthcare. Smart cards may provide strong security authentication for single sign-on (SSO) within organizations. Several nations have deployed smart cards throughout their populations.

This (Peter Hammill album)

This is the 25th studio album by Peter Hammill, released on his Fie! label in 1998. There is a large variety in the compositions, ranging from the minimalism of the final song, "The Light Continent", to the rough, almost Nadir-like sound of "Always is Next", the complex "Unrehearsed" and the ballad "Since the Kids". Peter Hammill performed the song "Unrehearsed" live many times. "Nightman" can be heard on the live-album Veracious (2006).

Traffic Operational Command Unit

The Traffic Operational Command Unit (OCU), formally known as CO15, was the Road Policing Unit for the Metropolitan Police Service.

On 1 December 2014, Traffic OCU was merged with the Safer Transport Command (STC), to create the new Roads and Transport Policing Command (RTPC).

Traffic stop

A traffic stop, commonly called being pulled over, is a temporary detention of a driver of a vehicle by police to investigate a possible crime or minor violation of law.

Traffic violations reciprocity

Under traffic violations reciprocity agreements, non-resident drivers are treated like residents when they are stopped for a traffic offense that occurs in another jurisdiction. They also ensure that punishments such as penalty points on one's license and the ensuing increase in insurance premiums follow the driver home. The general principle of such interstate, interprovincial, and/or international compacts is to guarantee the rule "one license, one record."

Transport Act 1968

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Trathens Travel Services

Trathens Travel Services was a Devon, England based bus and coach operator, taken over in 1996 by Scottish-based Park's Motor Group. The family owned group came to national attention after running express coach services from Plymouth to London, in light of the Transport Act 1980.

VDO (company)

VDO is a brand of Continental Automotive. Products under the brand include automotive electronics and mechatronics for powertrain, engine management system, fuel injection Systems. A full range of Tachograph and Data Management products and Telematics. Also since 1958 VDO supply Marine solutions for pleasure boats, yachts and sailing boats, wherewith with over 60 years of experience VDO stands as one of the oldest marine suppliers in the industry. In 2018 the Marine business has been separated from VDO and brand of VDO Marine has been established. VDO Marine products are made by Swiss manufacture veratron AG.

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