Tachograph Calibration & Testing

Keeping your tachograph legal and accurate

Every vehicle over 3.5 tonnes used for commercial purposes must have a calibrated tachograph — and that calibration must be renewed every two years. Operating with an out-of-date calibration is an offence that can result in fines, prohibitions, and points against your operator’s licence.

What calibration involves

Tachograph calibration checks and adjusts the accuracy of the speed and distance recording against a measured course. The tachograph must record within defined tolerances set by EU regulation. After calibration, a calibration plaque is fitted to the vehicle showing the date of calibration, the workshop that carried it out, and the next due date.

Digital and analogue

We calibrate both digital tachographs (Stoneridge, VDO/Continental) and the older analogue chart recorders still found on some vehicles. Digital tachograph calibrations include a download of the vehicle unit data, which operators are legally required to collect at least every 90 days.

When calibration is required

Every two years as standard; after any tyre size change (different rolling radius affects distance recording); after a tachograph repair or replacement; if the vehicle’s characteristic coefficient (W factor) changes; and if the calibration plaque is damaged or illegible.

Installation and repair

We also install new tachograph units and carry out repairs to existing installations — including speed sensor replacement, wiring repairs, and display unit faults.