This topic

Home Hub 3 & Battery Back Up - Incompatible power connection

matty1961 — Wed, 03 Jun 2026 16:07:03 GMT

So, I've just received a Home Hub 3 for my flat and thought I'd try it at my mate's house, who has a battery backup.

How absolutely stupid - the plug on the Battery Backup is larger than the power socket for the Home Hub 3.

Why didn't they keep the sockets and plugs the same size?

Now, they'll have to send out more cables to replace the ones already supplied with the battery backup to accommodate the smaller socket.

Stupidity at its finest.

I give up!

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

pddco — Wed, 03 Jun 2026 22:51:22 GMT

Haven’t got a Smart Hub 3 myself. But have got a BT supplied Battery Backup. It came with two leads. One marked for a Smart Hub 2 and the other larger one for the Smart Hub Plus - the EE Router. I’m wondering if in fact the larger plug will also fit the SH3. That’s assuming of course you’ve got that lead…

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

matty1961 — Thu, 04 Jun 2026 07:31:42 GMT

If you read my original post, I was saying the Smart Hub 2 plug does NOT fit the Smart Hub 3. The Smart Hub 3 has a smaller socket.

I don't know the plug size on an EE Router

Therefore, BT are going to have to provide a new lead, which is an extra expense.

All the designers had to do was use the same socket on the 3 as there is on the 2

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

licquorice — Thu, 04 Jun 2026 08:09:10 GMT

And you clearly didn't read @pddco response

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

matty1961 — Thu, 04 Jun 2026 08:13:09 GMT

HOW can a larger plug work on the Hub 3, as the socket on the Hub 3 is smaller than the Hub 2

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

licquorice — Thu, 04 Jun 2026 08:20:52 GMT

Clearly none of us can read! 😀

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

WSH — Thu, 04 Jun 2026 10:41:27 GMT

So, you lot, how about posting something useful, like telling us the actual size of the plug on the SH3 power unit?

The SH2 was a 3.0 x 5.5mm, an unusual size, as you've noticed. (More common in the US, I believe).

It sounds as though the SH3 is back to being a 2.1 or a 2.5mm, (like the Home Hub 5b), but which?

(You can measure them by inserting a metric drill bit into the plug. If a 2.5 doesn't fit, it will be a 2.1).

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

garybs29 — Thu, 04 Jun 2026 11:12:42 GMT

@matty1961wrote:
So, I've just received a Home Hub 3 for my flat and thought I'd try it at my mate's house, who has a battery backup.
How absolutely stupid - the plug on the Battery Backup is larger than the power socket for the Home Hub 3.
Why didn't they keep the sockets and plugs the same size?
Now, they'll have to send out more cables to replace the ones already supplied with the battery backup to accommodate the smaller socket.
Stupidity at its finest.
I give up!

Honestly I give up too. I'm sure if someone has a hub 3 they'll get sent the correct cable. There's probably a newer version of the backup too!

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

pddco — Thu, 04 Jun 2026 16:06:55 GMT

Sorry @matty1961 . @licquorice is spot on. I’d not read it right. But just had a look and the EE Smart Hub Plus has a smaller plug than the SH2. The Cybex backup battery was supplied to me with a lead for a SH2 and a Smart Hub Plus. So perhaps the lead for the SH Plus is also compatible with the SH3?

Re: Home Hub 3 & Battery Back Up - Incompatible power connection

pddco — Thu, 04 Jun 2026 17:06:51 GMT

Just measured the plug for the EE Smart Hub Plus. Its outside diameter is 3.5mm.

The Smart hub 2 plug measures 6.0 mm outside diameter.