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Why is the data just informative? — tachograph block

Updated today

In the Online Map, after selecting a vehicle, you can see different types of data collected by the vehicle’s telematics device.

One of these is the tachograph data, shown in the tachograph block, which gives you an overview of driving and rest times.

This can be helpful for understanding driver activity, but it’s important to note that this data is only an estimation and should not be treated as fully accurate.

It is:

  • A planning tool for dispatchers — useful for making routing and scheduling decisions.

  • NOT a legal document — official compliance records come from tachograph file downloads (DDD files) and printouts.

  • NOT perfectly accurate — small discrepancies with the actual tachograph display are normal and expected.


Why they can be inaccurate

There are several reasons why the prediction might not perfectly match reality:

Reason

Explanation

Data delay

There is always a small delay between what happens in the vehicle and when the data reaches our servers. This is usually seconds to minutes, but can be longer with poor mobile coverage.

The system assumes the last known activity continues

If the last data received said "driver is driving" at 10:00, and no new data arrives until 14:00, the system assumes the driver has been driving for 4 continuous hours.

In reality, the driver might have stopped — but the system has no way to know without new data.

This is the most significant source of inaccuracy.

Manual tachograph entries are not captured

Drivers can make manual corrections on their tachograph (e.g., marking a past period as rest).

These corrections only appear when DDD files are downloaded, not in the live data.

Ignition-based assumptions

When the ignition turns off, the system assumes the driver is resting. This is usually correct but not always (e.g., the driver might be doing paperwork in the cab with the engine off, which should be "work" not "rest").

Driver card not inserted

If the driver's card is not in the tachograph, the system cannot track their activities properly.


When to trust predictions

Situation

Trust level

Why

Vehicle is actively driving and sending data regularly

High

Fresh data, the system has a clear picture

Vehicle stopped recently, driver is resting

Good

The "rest" state is shown until something changes

Comparing with the tachograph display for exact minutes

Moderate

Small differences are normal; don't expect an exact match

Vehicle has been offline for several hours

Low

Data is stale; the system is guessing based on old information

Driver card is not inserted

Low

Activities cannot be properly attributed

"NO DATA" is shown

None

The system explicitly says it cannot make a prediction


What is DDD file data?

DDD files are the official data files downloaded from driver cards or vehicle tachograph units. They contain the complete, authoritative record of all activities.

When DDD data is available, the system merges it with live data to improve prediction accuracy. Without it, the system relies solely on live data, which may have gaps or less precision.

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