Surge Protectors Aren't Forever.
Surge protectors aren't magic. When they receive a power surge from the electrical outlet they’re plugged into, they have to do something with that extra voltage to get rid of it and shield the connected devices from it.
A typical surge protector uses a component called a metal oxide varistor (MOV). When the voltage spikes, the surge protector effectively diverts that extra voltage to the MOV component. This component degrades when it’s exposed to either a small number of large surges or a larger number of smaller surges. The additional energy doesn’t damage your devices — it stays in the surge protector, where it degrades the MOV.
In other words, your surge protector can only absorb so many surges before it stops functioning as a surge protector and starts functioning as a dumb power strip that’ll let everything through to your devices.
Read More Here: http://www.howtogeek.com/212375/why-and-when-you-need-to-replace-your-surge-protector/
NOTE: At RJM Computers we stock a large line of surge protectors and uninterruptible (battery backup) power supplies. Stop in today! http://rjmelectronics.com/power.html