Power Protector for Equipment and Electronics

I have always wondered if power protectors for electronics work and protect equipment.

Within a week of buying it, there were several electrical failures due to the rains and storms; causing the power to go out and the equipment to turn off/on when the light came back. Previously, the equipment went off every time the electricity fails, with a high risk that it could damage the equipment (refrigerator, air conditioning or electronics).

Now with the protector when the electricity goes out, the equipment loses electricity but has a protection delay of 3 minutes and what it does is that after the electricity is stable for more than 3 minutes; The protector sends electricity back to the equipment and prevents electrical shocks from damaging the equipment and its electronic components.

After this I learned that there are several types of protectors, 110V and 220V, single-phase and three-phase that help protect the equipment against these electrical changes and the more advanced 220v also have the option of modifying the protection delay time and the voltage level to be protected, above or below ideal current.