PPS stands for Programmable Power Supply. With PPS the charger itself can intelligently communicate with the power supply at short intervals to ensure that the power being supplied can dynamically change to the demands of the connected device.
The maximum delivery of this charger is 45W / 6A. It is important to recognise that the largest 15v-20V output achievable is only realised when the vehicle input is 24V (this is usually in large trucks). The charger is compatibe with vehicles of 12V ? 24V.
To get the very best out of the charger ensure that you are using a compatible high quality cable.