Other technical aspects
This page presents some technical aspects of the digital tachograph that are not directly related to data recording and the use of smart cards, such as:
- Display / Displaying
- Printer / Printing
- External Interface
- Time Adjustment
- Electromagnetic Compatibility
Display / Displaying
The display includes at least 20 characters. The minimum character size is 5 mm high and 3,5 mm wide. The display is always be ON when the vehicle is moving.
The recording equipment displays:
- Default data,
- Data related to warnings,
- Data related to menu access,
- Other data requested by a user.
The recording equipment briefly displays the card holder name at card insertion.
When no other information needs to be displayed, the recording equipment displays, by default, the following:
- The local time (as a result of UTC time + offset as set by the driver),
- The mode of operation, (in the case where the display width does not allow to display by default the mode of operation, the recording equipment briefly displays the new mode of operation when it changes),
- The current activity of the driver and the current activity of the co-driver,
- Information related to the driver, that is to say if his current activity is DRIVING, his current continuous driving time and his current cumulative break time, or if his current activity is not DRIVING, the current duration of this activity (since it was selected) and his current cumulative break time,
- Information related to the co-driver, that is to say the current duration of his activity (since it was selected).
The display of the recording equipment uses the pictograms or pictogram combinations.
It is possible to display print-outs content, line by line. If the display width is less than 24 characters the user should be provided with the complete information through an appropriate mean (several lines, scrolling, .). Printout lines devoted to hand-written information may be omitted for display. It should be possible to display selectively on request:
- The UTC date and time,
- The mode of operation (if not provided by default),
- The continuous driving time and cumulative break time of the driver,
- The continuous driving time and cumulative break time of the co-driver,
- The cumulated driving time of the driver for the previous and the current week,
- The cumulated driving time of the co-driver for the previous and the current week,
- The content of any of the six printouts under the same formats as the printouts themselves.
Printer / Printing
The detailed format and content of these printouts are specified in Appendix 4 of the Annex IB. Additional data may be provided at the end of the printouts. Additional printouts may also be provided by the recording equipment, if clearly distinguishable from the six aforementioned printouts.
The driver activities from card daily printout and events and faults from card printout are available only when a driver card or a workshop card is inserted in the recording equipment. The recording equipment updates data stored on the relevant card before starting printing.
In order to produce the driver activities from card daily printout, or the events and faults from card printout, the recording equipment:
- Either automatically selects the driver card or the workshop card if one only of these cards is inserted,
- Or provides a command to select the source card or select the card in the driver slot if two of these cards are inserted in the recording equipment.
The printer should be able to print 24 characters per line. The minimum character size should be 2,1 mm high and 1,5 mm wide. Printouts retain their dimensions and recordings under normal conditions of humidity (10 to 90 %) and temperature. It is also be possible to add handwritten notes, such as the driver's signature, to these documents.
The recording equipment manages paper out events while printing by, once paper has been re-loaded, restarting printing from printout beginning or by continuing printing and providing an unambiguous reference to previously printed part.
When the recording equipment does not include speed and/or odometer display functions, the recording equipment provides output signal(s) to allow for displaying the speed of the vehicle (speedometer) and/or the total distance travelled by the vehicle (odometer).
The Vehicle Unit (VU) is also able to output the following data using an appropriate dedicated serial link independent from an optional CAN bus connection, to allow their processing by other electronic units installed in the vehicle:
- Current UTC date and time,
- Speed of the vehicle,
- Total distance travelled by the vehicle (odometer),
- Currently selected driver and co-driver activity,
- Information if any tachograph card is currently inserted in the driver slot and in the co-driver slot and (if applicable) information about the corresponding cards identification (card number and issuing Member State).
The time adjustment function allows for adjusting the current time in amounts of one minutes maximum at intervals of not less than seven days. The time adjustment function allows for adjusting the current time without limitation when using a workshop card.
The Vehicle Unit is fully operational in the temperature range from – 20 C° to 70 C°, and the motion sensor in the temperature range – 40 C° to 135 C°. Data memory content is preserved at temperatures down to – 40 C°.
The recording equipment is fully operational in the humidity range 10 % to 90 %.
The recording equipment is protected against over-voltage, inversion of its power supply polarity, and shot circuits. The recording equipment shall conform to Commission Directive n°95/54/EC of 31 October 1995 adapting to technical progress Council Directive n°72/245/EEC, related to electromagnetic compatibility, and shall be protected against electrostatic discharges and transients.