Radars are installed on the roads so that those of us who drive moderate our speed according to what is established by the highway code, which results in safer driving, fewer accidents and of course, fewer fines. So when we see a radar (or the corresponding application warns us), the normal thing is to reduce the speed.
How much should you reduce your speed on a radar? It should be remembered that the speed indicated by radar applications and therefore displayed in Android Auto, is not that of the car’s speedometer. And in turn, it is normal for the speed indication of the section to appear in front of the radar or even fixed on the radar itself.
But that’s it there is a margin of error between the speed indicated by the speedometer and that detected by a radar, which opens the door either to not receiving a fine even if we technically exceed the speed, or to being able to claim this penalty. And this happens with everyone: fixed radars, speed cameras or section, mobile and even drones.
How fast do radars jump?
East the law itself states that there must be a margin of error so that when the radar jumps, it is because the maximum speed determined for that road has been exceeded. Come on, if you cross an area with radar and limit of 80 km/h and you drive at 81 km/h according to the speedometer of your car, you will not receive a fine.
This is where the rule of seven and five comes into play. In 2016, the General Directorate of Traffic explained in a publication on X/Twitter what margin it was: the key is in the rule of seven (We will see later that even if there are nuances, this one is the most important).
In other words, for speeds below 100 km/h you have to add 7 km/h to the speed indicated on your speedometer for the radar to trigger and if you are above 100 km/h, then you will have to add 7% of speed. We see it better with some examples: if the speed limit is 50 km/h, the radar will jump above 57 km/h, but if you are driving at 120 km/h, then the barrier is above the limits of 128 km/hh
This regulation has been in effect since the modification of the Highway Code in 2014, since previously this margin reached 10 km/h. So, if you want to drive more carefully and avoid the fine for speeding, which we remember is at least 100 dollars, it can also be up to 6 points less on your license or in prison, follow the rule of seven
The choice of seven is not a random number.: on the one hand, speeds below 100 km/h are difficult to perceive for mobile radars and, in addition, the errors allowed in car speedometers vary between 3% and 7%, the latter being the most unfavourable and most common in older vehicles.
Although the rule of seven is the best known and most important, in reality the margins of error differ depending on the radars, here is a summary of the ministerial decree ICT/155/2020 where you will see that in practice it is a mixture of the rule of seven and the rule of five.
- Fixed radars: margin of error of 5 km/h at speeds below 100 km/h and 5% above.
- Mobile radars: margin of error of 7 km/h below 100 km/h and 7% above.
- Section radars: margin of error of 5 km/h at speeds below 100 km/h and 5% above.
- Drones and Pegasus: 10% margin of error.
Of course, according to the DGT, In their sanctions, they always take into account the rule of sevenSo this is the one you should apply without fear.
By | The newspaper
Cover | DGT
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