Try out the tracker on your personal car, as Zark stated, not all trackers have the same accelerometer, I have found out that even within the same tracker manufacturer, accelerometer measurements are different. A few tips when using the accelerometer in a tracker:
1) First and most important step is to make sure you calibrate the tracker properly; each manufacturer has its own calibration procedure. Read the instructions carefully.
2) Configure your tracker to send data to the server for anything above .25 g´s...you can reconfigure this value once you finish doing your tests and get an idea how little is too little and how much is too much.
3) On your phone, install any app that can measure g forces and drive your car using your cell phone to measure the g forces when braking, accelerating and cornering. This will help you get an idea of how many g forces a car can experience...you will learn very fast that cornering from .3 g´s to .4g´s takes a lot of effort, it´s not easy to be consistent. Braking is also difficult, depending on tire and road conditions you can have very high peaks but also super difficult to be consistent in hitting the same amount of g forces.
4) Plan synthetic tests, for example. Try to corner 3 times hitting the maximum g forces that you can produce, measure them with your cell phone and then compare the data with what the tracker sent to your tacking platform, do the same for acceleration and braking.. You will learn a lot by doing this....It´s hard to determine what "hard braking" is vs "dangerous braking" is.
5) Analyze your data and with everything that you learn from the synthetic tests, you can reconfigure your tracker to report anything above "X" g forces and also get an idea how to configure your values within Wialon´s EcoDrive app.
These 5 steps will help you understand not only the technical part, but also help you understand that EcoDrive will behave different depending on the vehicle. A couple of extreme examples: Concrete mixers and passenger buses have a loooot of body roll, this will impact how you interpret cornering values.
Long story short, EcoDrive is not just a g force value that you can standardize for all vehicles, its a solution that you need to analyze per customer and vehicle type.
Hope this helps