@Keith_Beddoe I agree.
A typical UPS with mains voltage output might be appropriate if other devices need to be powered as well as the hub, and then only for short power outages. If all that is required is power for the Hub to maintain telephone service then the simpler and cheaper solution is the float-charged lead-acid battery, not a solution available off the shelf (hence the quest by some contributors for the unusual barrel connector used on the Smart Hub 2).
For info I've just found a supplier (Power Adapters UK) who stocks an adapter to convert a 5.5mm o/d x 2.1mm pin (as used on my Power Inspired IP-2100-12G (and several other generic power supplies) to 5.5mm o/d x 3mm pin, which is the correct plug for the BT Smart Hub 2. It should be with me tomorrow so I'll post again if it works.
Also maybe of interest - Power Inspired is about to bring out a new Lithium-ion UPS, the IPower-H. They state "The iPOWER-H is fitted with a higher capacity 3350mAh 18650 cell for extra runtime. In tests it has been shown to power a typical WiFi router/hub for an hour. This allows communication companies using ONTs to meet the OFCOM3 requirement of ensuring that the end user is able to make and receive phone calls for 60 minutes in the event of a power outage."
My current IP-2100-12G is rated at 2600mAh, so a fairly substantial increase in runtime. According to the specs the new one is same size and weight.
I've seen a few Lithium-ion (li-ion) battery options too on these mini-UPS units like:
TalentCell Mini UPS Uninterrupted Power Supply 27000mAh
There's several models most come with the appropriate 12v barrel plugs. Reviews seem to be pretty good.
Just make sure you get one with a UK plug if buying for someone else.
Hopefully the large manufacturer's will start doing something like this.
The TalentCell unit looks useful for anyone needing to power multiple devices; it has some good reviews (but also some pretty bad ones).
I noted that the TalentCell mini-UPS comes with 2 DC cables, but they're both fitted with the 5.5mm o/d x 2.1mm pin plugs. In the sales blurb on Amazon they state "if the size of your device input port is not DC 5.5 x 2.1mm, you need to buy the proper chord or adapter separately.". In my experience that means "go find one" not "we can sell you one". I went to the TalentCell website, but couldn't find any mention of available accessories (or indeed of their mini-UPS!).
It's always worth checking directly with the supplier to make sure the UPS comes with either a cable or adapter that fits the BT Smart Hub. Most (if not all) have the "standard" 5.5mm/2.1mm plug on the end of the DC power cable, so either a replacement DC cable or an adapter is necessary. You'd think it would be pretty easy to get hold of a suitable adapter, but although there are many adapters out there very few accommodate the 3mm pin in the BT Smart Hub 2 DC input socket - the correct plug size for the SH2 is 5.5mm o/d x 3mm pin; a plug sized at 6.3mm x 3mm pin will also work, although it's a tight fit (I've also successfully used a plug described as 6.2mm o/d x 3mm pin, but I believe the 6.2mm and 6.3mm are actually the same - mine both actually measured 6.25mm. The adapters all need to fit onto the 5.5mm x 2.1mm pin DC supply cord plug. Issues I've had in finding the correct adapter are:
Apologies - corrections required; thanks to those who spotted my errors.
First, the supplier is Power Adaptors UK, not Power Adapters.
Second, I did point out to them I was looking for an adapter to match a 3mm pin on the hub socket. They've just come back to me telling me that the 5.5mm o./d 3mm item has a 3mm i/d but also has a centre pin (so won't fit) and is sometimes referred to as a 5mm x 1.1mm jack. Very confusing.
So it seems that the only available adaptor that will fit the hub is the 2.1mm x 5.5mm to 3.0mm x 6.3mm DC Power Plug Adaptor. Fortunately Power Adaptors UK does have this available as a single item (i.e. not as part of a set).
@JB2016wrote:@Keith_Beddoe I agree.
A typical UPS with mains voltage output might be appropriate if other devices need to be powered as well as the hub, and then only for short power outages. If all that is required is power for the Hub to maintain telephone service then the simpler and cheaper solution is the float-charged lead-acid battery, not a solution available off the shelf (hence the quest by some contributors for the unusual barrel connector used on the Smart Hub 2).
After a lot of thought that's exactly what I've gone for. Best not post a link but that well known company named after a big river sell them for about £90. It means I can have UPS supply for the BT hub, my cordless BT phone hub and one spare.
Oh look the mainstream media have finally caught up with this whole issue, could be time for BT and it wasn't like they weren't warned
https://www.mirror.co.uk/money/bt-end-landline-phones-sparking-25544885
You would think the journalist's would know how to do some research & have a go at who's actually instgating all this......
As the old saying goes, 'never let the truth get in the way of a good story'
Journalists need to read these pages, to get the correct facts.
This two page article explains it https://www.draytek.co.uk/information/blog/the-end-of-analogue-phone-lines-pt1
Also https://www.openreach.com/fibre-broadband/retiring-the-copper-network
Just as a side issue, for all these years, people have been getting free electricity down their phone lines. All it means now is it has to be supplied by the customer, like any other appliance.
An interesting fact, slightly off topic, from the days of the GPO, that some may remember. If anyone was caught intercepting phone calls, all they could be charged with was "Stealing a quantity of electricity, property of GPO Telephones" How times have changed 😉