I have the following power sources:
- AC/DC adapter (5V-36V)
- 5V USB
I connected the two power inputs properly (diode) but I am not sure about the reverse polarity protection. I haven't found any sources on the internet which mentions if there is any problem with ground short circuit. My problem is if neither the adapter nor the usb is isolated then reverse polarity connection could cause short circuit through the zero line in the "wall".
So what is your opinion about this? Are the adapters isolated? How can I protect the circuit if the power sources are not isolated?