The tech behind how black boxes know the speed limit

Telematics insurance is really clever. It uses a device called a black box to measure how fast you’re going, what time you drive, how sharply you’re braking and how you accelerate - whenever you’re out on the road. If you have one installed by WiseDriving, the better you do all these things, the cheaper your car insurance can be.
 
How fast you drive and how you navigate the roads is an important factor when our system is working out how much you should be paying each month - but how does a black box know the speed limit? Here, we’ve broken it down.
 
How does a black box know the speed limit?
Black boxes use GPS to track you while you’re driving -this means they can measure how fast you are moving on the roads. This is then compared to the road’s legal speed limit to determine if you’re driving over this or under it.
 
Think of it like when you use a satnav or Google Maps on your phone for directions - these devices use GPS to track your whereabouts and many calculate how fast you are driving and the limits on the roads you’re driving on to determine when you will arrive at your destination.
 
This is also how these boxes understand how sharply you’re braking, as they can see how quickly you’re slowing down and where on the road. If you’re hitting the brakes at the last minute, it’s likely you’ll be closer to the junction instead of a few hundred yards before it and this can all be tracked via GPS.
 
All of this data is recorded live and then stored on a secure server which our team can access later if needed. It’s a great way of keeping tabs on how you’re driving and working out that all important driving score later.
 
The benefits of your driving being tracked
Having your driving tracked can feel like a bit Big Brother for some people but it’s actually really helpful.
 
It can save you money
Driving below the speed limit means you’ll enjoy a better result when we calculate your driving score. We review how much you pay for your car insurance every month - and careful driving means cheaper insurance.
 
It can make you a safer driver
Slowing down and being conscious of the speed limit means you’ll drive a little more carefully, slow down in time and take corners safely. It also reduces the risk of being stung with a ticket on roads, as you always stay below the legal speed!
 
It can keep other road users safe
These limitations are created for a reason and driving while being aware of them reduces the chances of you ending up in an accident. A sharp bend, for example, may require you to slow to 50mph to avoid you losing control, while a road next to a school may require you to drive at 20mph between certain times of day to keep children safe.
 
Understanding how black boxes work is important if you have one installed. Always be aware of the speed requirements where you’re driving, maintain a great driving score and ultimately stay safe!

Posted on June 12, 2018


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