Does Maestro Mini have any protection against connecting wires wrong way or using too big voltages etc?
I am not sure if you are asking about the logic side of the Maestro or its servo connections. The VIN pin can accept 5-16V to power the Maestro’s logic side, and the Maestro does not have any reverse-voltage or over-voltage protections. The servo power rails are isolated from the Maestro logic; the voltage you connect to it should conform to the needs of the servos you have connected. The servo channels are not polarized in any way to prevent your servos from being connected backwards.
I found this text below and it talks about Pi-Face and i wanted to know if Maestro has same things.
“isolates the GPIO pins and protects the Raspberry Pi from damage”
No, we do not have anything like that add-on board for our Maestros, and the Maestros do not have this protection feature built-in.