Hi,
i have a BrickPi+ and a Raspberry Pi 3.
My question is if I understand the powering all right.
Can I power my Raspberry Pi 3 (and Brick Pi) through only a (wall) power supply on the Raspberry Pi? Just for programming?
And I have to use the battery pack in addition when I want to use the Motors and sensors too?
Sorry for my bad English… 
Thanks for Help!
You can do your programming and motor/sensor testing just with your Raspberry Pi power adapter. If you run with both the power adapter and the BrickPi batteries, the batteries will last for weeks.
Uhh, JohnC I thought said you must have the battery plugged in for running motors. Powering BrickPi Motors
Ok, thanks for answering @rolly @graykevinb ! 
I just wanted to know if the BrickPi+ regulates the power (coming from the battery pack) automatically either powering the RPi with power Adapter or not?
And that means as a result, that it’s not important how much volts I attach to my RPi? The BrickPi supplies the rest?
You can program the Raspberry Pi with BrickPi+ using just a 5v power supply (as long as it provides enough current that the Raspberry Pi is stable).
However, if only running on 5v, it is best to not run motors, and a couple sensors might not perform as expected. For running or testing a robot after you have programmed it, it is recommended that you use either a battery pack or a regulated wall adapter that can source enough current for the Raspberry Pi, BrickPi+, and any sensors and motors you are using (note that each Lego NXT and EV3 motor can draw up to about 1A under heavy load). The power supply should be about 9v (7.2v-12v should work, but the motors are designed for 9v).
It should be fine to have the Raspberry Pi connected to a 5v power supply at the same time as the BrickPi+ is connected to a 9v power source. Running like this has the advantage of the BrickPi+ being able to keep the Raspberry Pi running stable even if the 5v USB power is inadequate.