I am planning lessons for a primary school (ages 9-12) code club around Scratch and the Explorer HAT Pro, and have some questions about how it deals with power draw levels and protection against overloading it. As I am planning to unleash inquiring young minds on these, I wanted to understand how this HAT handles potential overloading? The specs say the 4 x 5V outputs can supply 500mA overall between them, and that the motor controllers can supply 200mA (per motor?). Does the board limit this load safely? Most motors have a stall current over 200mA and I don’t want to see the controllers burning out. I planned to start with the STS Pi kit (motors included) but these are quoted as having a stall current of 900mA (at 6V), so likely to be well over 200mA at 5V when driven from this HAT.
Also, are the 5V outputs protected from overload if a child shorted them to ground for example? I am planning to use 3A power supplies (the Official ones) which should provide enough current to run everything (Pi3, Explorer HAT Pro, 2 motors plus some LEDs and a buzzer). Is there anything I need to be wary of that could cause damage to the hardware? I plan to mask off the 3.3V connections on the HAT with tape to avoid them being used.
Finally, I have seen projects mention driving servors from these HATs too. So we might be trying that at some point.