What about a mobile phone with a PAYG sim that does not need a monthly top up, such as 1pMobile or Giffgaff?

I've been considering a EcoFlow, whilst not a true UPS they will switch over in such a short time it's near enough, and will power phone/ont/router for hours.

EcoFlow’s are great indeed. I use a Delta2 with an extra battery for off-grid stuff and the app etc is all very good. I run it for days on end. One of them will standup a typical home broadband setup for many, many days. Eons better than a a typical standby AC UPS.

However they aren’t cheap at all. So they won’t suit everyone’s budget, especially just to standup a broadband connection which may only have a power fault event very rarely.

I use and am happy with my Cyberpower 700

In reply to a post by Andrue:

but it's hardly going to see me through a serious power cut.

Consumer-type UPS's are meant to give you time to shut down gracefully, not to keep you going through an extended loss of power. You need some serious batteries (or a motor-generator set) to do that.

Not sure if you could hang a few vehicle-type lead-acid accumulators on that sort of UPS, but better solutions have been suggested here.

In reply to a post by billford:

In reply to a post by Andrue:

but it's hardly going to see me through a serious power cut.

Consumer-type UPS's are meant to give you time to shut down gracefully, not to keep you going through an extended loss of power.

Indeed and is not just chap consumer AC type UPS either. Commercial “on-line” UPS’s costing from hundreds to many hundreds of thousands, all operate on the same principle - they are short term (typically less than 30 minutes) duration reserves of power designed either for the mains to come back in that time - or an alternative - like standby diesel to come on steam and take up the load.

By and large AC type UPS are designed around this “short and sharp” standup philosophy.

The fallacy that many folks fall into is that they look at the full load runtimes and divide it by (the very modest) load requirements of say broadband kit and arrive at monster theoretical up times. Typically they don’t work that way as the lead acid battery at the heart of the unit, has a working voltage range/operating window which is quite narrow and the UPS shuts down relatively early to avoid deep discharge of the pack.

I'm using this type which is designed for CCTV I think.

http://i.imgur.com/iSSU8zT.jpg

http://i.imgur.com/QAyxMOp.jpg

http://i.imgur.com/bDqLRGd.jpg

It runs my router and ONT for approx. 1 hr.

I also have an APC 700VA unit which gives mains out and last for approx. 15 mins.

In reply to a post by smouty:

I'm using this type which is designed for CCTV I think.

http://i.imgur.com/iSSU8zT.jpg

http://i.imgur.com/QAyxMOp.jpg

http://i.imgur.com/bDqLRGd.jpg

It runs my router and ONT for approx. 1 hr.

I also have an APC 700VA unit which gives mains out and last for approx. 15 mins.

Thank you for this - appreciate you sharing. I shall investigate!