We've all heard it before when troubleshooting a router:
unplug the power cable from your router
wait 30 seconds
plug it back in.
More often than not, this fixes whatever problem we have. But why is that?
It’s all about capacitors.
A lot of modern technology contains capacitors! These are
like energy buckets, little batteries that fill up when you put a current
through them, and discharge otherwise. 30 seconds is the time it takes most
capacitors to discharge enough for the electronics they're powering to stop
working. That's why when you turn your PC off at the wall, things like an LED
on your motherboard take a few seconds to disappear. You probably could wait a
different time, but 30 seconds is the shortest time you can be sure
everything's discharged.
So, it's all
about capacitors. There's no magic trick involved where you have to wait
exactly 30 seconds for the gremlins to disperse.