The moment supply is restored is electrically busier than the outage itself, and it is the reason a certain amount of equipment fails on restoration rather than during the failure.
Everything that was switched on when the power went out is still switched on. When the supply comes back, all of it starts simultaneously. Motors draw several times their running current during the first fraction of a second while they come up to speed, and heating elements draw their full load immediately. On a street where every house is doing this at once, the local network sees a demand spike far above normal.
That spike shows up inside the house as a brief voltage sag, sometimes deep enough that electronics reset or refuse to start cleanly. It can also arrive as the opposite problem, a transient overvoltage caused by switching operations upstream as the utility brings sections back in stages.
Utilities restore in stages for exactly this reason, energising portions of the network in sequence rather than all at once. It is also why power sometimes returns, drops again within a minute and then returns for good.
There is a practical response available to anyone. Switching off or unplugging sensitive equipment during an outage, particularly computers, televisions and anything with a motor, removes it from that first surge. Leaving a single lamp switched on gives a visible signal that supply has returned so the rest can be brought back deliberately.
Refrigeration deserves a note of its own. A compressor that stops under pressure cannot restart against that pressure until it has equalised, which takes several minutes. Power returning inside that window causes the motor to stall and draw locked-rotor current until its overload protector opens. Repeated attempts are what damages compressors.
Anything that fails to come back after restoration, or comes back behaving oddly, is worth investigating rather than repeatedly cycling.
Extended outages add a separate concern around anything that was running when supply failed. A stove burner, a space heater or an iron left switched on becomes an unattended appliance the instant power returns, which may be hours later and in the middle of the night. Walking through and switching those off is the first thing to do once the lights go out.
More on this: https://oukirilimetodij.edu.mk