Do not get me wrong, surge protectors are OK but you never know when they have had enough. The zena diode they contain has a finite number of joules of protection in it – how long it will protect depends on the number and size of hits it receives. The problem is there is no way of telling, so other than buying a surge protector with a massive joule rating you will never know if there is protection against the next thunderstorm. In Singapore 12 months was the max expected life of one and same in Mid West of US. In most parts of the UK (ex perhaps SE Midlands to Lincolnshire) I think five years might be a better number. I’d guess at two years for Lincoln the lightning capital of the UK.
My personal preference is for an ups as they link with your pc and give status reports. They also give time to handle short power outages or blips, and the better ones have easy to replace batteries.
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