topic Cyberpower battery backup cable in Broadband & Landline

Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 15:44:15 GMT

Hi all,

Can anyone please confirm for me that this cable:

https://ee.co.uk/products/battery-back-up-plus-connecter-cable-for-smart-hub-2-cable-only

...is the correct one to connect the Cyberpower battery backup unit BT are currently sending out? Many thanks.

@JimM11 @Xrayspecs

Re: Cyberpower battery backup cable

XRaySpeX — Sat, 22 Aug 2026 15:59:02 GMT

Well, it's for a Smart Hub 2 & only BT has a Smart Hub 2. So it must be!

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 16:03:48 GMT

Sorry, @XRaySpeX . It seems I wasn't clear enough there.

Yes, it says it's for the Smart Hub 2 BUT is it the correct plug for the socket on the Cyberpower battery unit connected at the other end? That's where the confusion is.

Re: Cyberpower battery backup cable

Schockwave — Sat, 22 Aug 2026 16:09:29 GMT

@Denzel99 , it actually says under specification that it is for the BT Smart Hub 2, so I cannot see what the problem is as the details does say that it connects to the smart hub and cyber power battery unit from what I have read under product details.

Re: Cyberpower battery backup cable

JimM11 — Sat, 22 Aug 2026 17:04:11 GMT

@Denzel99 This is the closest i can see, i have a set of CyberPower cables one was on the ONT and the Other on the EE Smart Hub6+, now the cable marked has Smart Hub (2) on it but was used to connect the ONT up, so one assumes the ONT/SH(2) are as it's the exact same plug for the ONT. The CyberPower plugs are right angled plugs but don't see a cable on Amazon. The one shown on the BT Forum is a NO NO, it's for the new BBU....

If the user has an ONT, get him to try the power connector from that in his BT Smart Hub 2, do not have access to one so cannot say. Cable is 1.5M long CyberPower supplied can take a picture if you need.

kenable DC Power Cable Male to Male 2.1mm x 5.5mm Connector Lead for Low Voltage Devices 0.5m Black: Amazon.co.uk: DIY & Tools

The Two pictures for you,

Re: Cyberpower battery backup cable

XRaySpeX — Sat, 22 Aug 2026 16:13:13 GMT

Key features

This cable connects your Smart Hub (2) and Full Fibre Connection Box (ONT/Modem) to the Battery Backup Plus, providing power during outages.
Compatibility: BT Smart Hub 2 (GRV9517UAC34) EE Smart Hub (SH20A)

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 16:31:23 GMT

Sorry, gentlemen. I don't seem to be making the point very clearly. The Smart Hub 2 end (or the ONT end, for that matter) is NOT the question. I know it will connect to the Smart Hub 2...that's what it says. The question is the other end. Does that plug fit the Cyberpower unit BT are sending out?

Let me try a different tac. Is the battery backup unit EE are offering the same one as the Cyberpower model BT are offering?

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 16:39:39 GMT

@JimM11 I can see the pictures now. That cable in the top picture looks like the the right thing. Where did you get that from?

Re: Cyberpower battery backup cable

JimM11 — Sat, 22 Aug 2026 16:46:58 GMT

@Denzel99 I fitted two units for my sister on the EE Hub/ONT, she is wheelchair bound Vulnerable status, with the CyberPower version DTB24U12V-BT3 you get Two cables with each BBU, as one set did everything then extra was left over, they are 5.5/2.1mm both sides for the SH2 marked version but was used to the ONT so i assume the same cable for both, the other is a 5.5/2.1mm to a 3.5/1.35mm as used to connect up a EE Smart Hub 6+ as it is now known new name...

Re: Cyberpower battery backup cable

JimM11 — Sat, 22 Aug 2026 16:55:01 GMT

@Denzel99 Link to the new BBU unit and it's cables, do not know if they are the same as a CyberPower connector wise though....

Search results for "battery backup"

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 16:55:32 GMT

Thanks, but this is where it's difficult to work out what is required.

The SH2 is not a 2.1mm plug. I know for a fact the SH2 is 3.0mm.

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 16:57:22 GMT

No, it's not.

That seems to settle it then. Thanks JimM11

Re: Cyberpower battery backup cable

JimM11 — Sat, 22 Aug 2026 17:36:41 GMT

@Denzel99 Confused now???? Take it you found it's a 2.1mm centre 5.5mm outer? The ONT power connector is for sure 5.5/2.1mm that is why i said get someone to pop that connector on a SH2 if it fit's that is, same voltage etc so would work powered or unpowered for testing....

Did your drill trick and a 3mm does fit all the larger connections, real snug fit, and the 2.5mm also as it would, do not have a 2mm one broken and lost now from the drill kit.

Re: Cyberpower battery backup cable

Denzel99 — Sat, 22 Aug 2026 17:32:48 GMT

I'm not sure where the confusion is coming from but the Smart Hub 2 is a 5.5 x 3.0 mm, the same as the old Home Hub 5 type A. The old Home Hub 5 type B was 5.5 x 2.5 mm. (I know, as I've actually measured all three in the past).

I expect the ONT will vary with the make/model but I'm not looking for a connector for the ONT.

This question has come up a number of times recently and I've yet to see a definitive answer. I tell you what, I'll get the OP to tell me the model number and I'll contact CyberPower support directly. I'll let you know what I find out.

Re: Cyberpower battery backup cable

JimM11 — Sat, 22 Aug 2026 18:09:01 GMT

@Denzel99 Looking like the 3mm is the one, and CyberPower are American, even in Amazon USA the 3mm one is not even showing up, if the ONT is a true 2.1mm plug then NO WAY it would fit into the back off the CyberPower so if the user has that he can test but UNPOWERED just cord pop on....

Units are the same number with a V1/V2/V3, last being the latest. User is welcome to this set just get's awkward dealing with the sending etc.

Re: Cyberpower battery backup cable

JimM11 — Sun, 23 Aug 2026 07:30:21 GMT

@Denzel99 The connector for the back off the CyberPower BBU is the same as the one for the BT Smart Hub 2, Barrel connector 5.5/3.0mm and for anyone who needs the output of the CyberPower is 12V Centre +ve on the cable.

DTB24U12V-BT1 Marked for ONT connection. cyberpower_bbu__for_fttp.pdf

DTB24U12V-BT2 Marked for the SH2 connection.

DTB24U12V-BT3 Marked for the SH2 or the Smart Hub Plus. Both cables supplied 5.5/3.0mm both sides 1.5M length. 5.5/3.0mm to 3.5/1.35mm 1.5M Length..... This is the best for covering as a single unit because it has both cable types supplied, Larger does a ONT/SH2 and the smaller does the EE Smart Hub 6 Plus and possible the SH3 latest when someone does a check on THAT....

The BT1-BT2 appear to be marked up wrong document and cables, where the BT2 does seem to be for the ONT, so going to leave as is above and the user has to do the due diligence to ensure correct connector ends match the documentation.

ONT is for sure a 5.5/2.1mm barrel but the 3.0mm fits no issue.....

Re: Cyberpower battery backup cable

Denzel99 — Sun, 23 Aug 2026 11:56:47 GMT

Excellent. That answers the question then. Thanks for that.