Drivers & hours
What is a tachograph?
A tachograph is the device fitted to a vehicle that records driving time, other work, breaks and rest. Its data is the evidence of whether drivers' hours rules have been complied with.
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<img src="https://fleetoptix.co.uk/glossary/tachograph/diagram.svg" alt="tachograph — diagram from FleetOptix" width="880" height="620" loading="lazy">
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<a href="https://fleetoptix.co.uk/glossary/tachograph">What is a tachograph?</a> — diagram by
<a href="https://fleetoptix.co.uk">FleetOptix</a>
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</figure>Modern units are digital and record to both the vehicle unit and the driver's own card, which is why both have to be downloaded at intervals and kept. The card holds the driver's record across vehicles; the unit holds the vehicle's record across drivers.
Downloading is not the same as analysing. Data sitting in a folder satisfies the requirement to hold records and tells nobody whether the rules were kept, which is the part that actually protects the licence.
Infringements are expected to be found, discussed with the driver and signed. A perfectly clean analysis across a whole fleet is itself a flag, because it usually means the analysis is not being done.
What goes wrong in practice
- Downloads happening but no analysis, so infringements are held rather than addressed.
- Infringements identified and never put to the driver, leaving no record that anything was done about them.
- Missing mileage between records, where a vehicle has moved with no card inserted.
- Manual entries for other work never made, making the record look like a driver's day started when the engine did.