topic Re: ONT extension DC power cable and Fibre cable used in Tech Help - Software/Hardware etc

ONT extension DC power cable and Fibre cable used

Dan_the_Van — Tue, 25 Mar 2025 10:39:25 GMT

Rather than adding a new Power socket for the ONT I am looking to extend the DC power cable, just need to confirm the specification, this cable would be no longer than 3 meters

From my research here and elsewhere suggests the PSU is 12v 0.5a 6w with DC jack size being 2.5mm x 5.5mm.

Just need to confirm the jack size of 2.5 x 5.5 mm and would this be usable for the various models of ONT used by Openreach?

The alternative to using a DC power extender would be to run the Fibre cable to a position where there is a power socket

Never being involved with Full Fibre installations be interesting to know what the Fibre cable used by Openreach within the house, how robust is it?

I think they use EZ bend products so the minimum bend would be that of a £2 coin. It will be run in trunking to protect it.

Thanks in advance

Re: ONT extension DC power cable and Fibre cable used

MisterW — Tue, 25 Mar 2025 10:53:52 GMT

@Dan_the_Van I believe Openreach will provide up to 10m of internal fibre. Normally they would clip to skirting boards but if you provide trunking then I'm sure they will use that. Your min bend radius might be a bit tight!. Are you aware of the diy fibre extension kits here https://www.premitel.uk/consultancy/expert-advice/how-to-relocate-the-ont-fibre-termination-point/ ? Looking at the box used to coil excess fibre it looks something like a 5cm bend diameter.

Not sure on the power connector specs and whether they are different depending on the ONT. Unfortunately I'm not at home so cant measure mine either...

Re: ONT extension DC power cable and Fibre cable used

bmc — Tue, 25 Mar 2025 10:59:35 GMT

@Dan_the_Van

This is my incoming fibre cable installed late 2017.

I would consider moving the ONT if your'e happy with the cable being stapled to the wall. Speak to the installer on the day.

Brian

Re: ONT extension DC power cable and Fibre cable used

outcast — Tue, 25 Mar 2025 11:51:48 GMT

@Dan_the_Van wrote:

From my research here and elsewhere suggests the PSU is 12v 0.5a 6w with DC jack size being 2.5mm x 5.5mm.

Just need to confirm the jack size of 2.5 x 5.5 mm and would this be usable for the various models of ONT used by Openreach?

@Dan_the_Van

Everything I'm finding suggests that typical Openreach ONTs use 2.1mm x 5.5mm connectors,

I've yet to see a 2.5mm x 5.5mm search result.

The most definitive answer I've found is in the Openreach SIN_506 document (attached below) on pages #28 to #30

showing that ALL Openreach ONTs are 2.1mm x 5.5mm

@Dan_the_Van wrote:

The alternative to using a DC power extender would be to run the Fibre cable to a position where there is a power socket

Another alternative would be running PoE (Power over Ethernet) to the ONT, then using a power splitter to locally provide the 12V to the ONT, that way only having one cable running to the ONT instead of separate ethernet and DC extension cord.

Example of a power splitter - Amazon : TP-Link TL-PoE10r

Re: ONT extension DC power cable and Fibre cable used

bmc — Tue, 25 Mar 2025 12:22:13 GMT

@Dan_the_Van

The other option could be the installer is happy to run the cable externally so it comes in where you desire. No internal cabling required.

If this is not possible, do not install the internal trunking until positions have been agreed with the installer. You should be able to quickly put it in place once the wall is drilled through. Could be done while the external CSP is being installed.

Brian

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Tue, 25 Mar 2025 13:32:07 GMT

Thanks all for your replies.

Currently the copper line is Underground and terminates to a B66B Junction Box at the front of my property, from there it goes internally to a small cupboard where the Master Socket 5c and MK4 faceplate is located. It is not clear to me if the cable internal run is via conduit to the Master Socket which is fitted to a stud wall

This cupboard is where my current Hub, WAP, NAS and VPN servers are located with a powerline connection (don't ask) to the garage and a garden WAP

So I am guessing using the outside wall to take the fibre cable to the same cupboard which has an outside wall,

So my concern on where best to locate the ONT in the cupboard as that's where I want it, I've concluded to have the Fibre cable run to the ONT position as this will be the simplest option. The fibre cable would be no more than 3 metres.

Thanks again for the suggestions.

Re: ONT extension DC power cable and Fibre cable used

bmc — Tue, 25 Mar 2025 13:48:42 GMT

@Dan_the_Van

My only concern would be if running it externally is if it needs to go round a corner of the house. Potential for damage at the corner. You speak to the engineer to agree a course of action. He might say no, not possible and that it needs to come is at the front wall. Have a back up plan just in case.

As to what happens in the cupboard - you are free to do what you like.

Brian

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Tue, 25 Mar 2025 13:55:37 GMT

@bmc

It can't can't go through the wall its the downstairs cloakroom no power, just a toilet and sink

Re: ONT extension DC power cable and Fibre cable used

bmc — Tue, 25 Mar 2025 13:59:57 GMT

@Dan_the_Van

Perhaps I should have said somewhere on the front wall.

However, this appears to strengthen the case for bringing the cable round the outside wall.

Brian

Re: ONT extension DC power cable and Fibre cable used

Baldrick1 — Tue, 25 Mar 2025 16:40:54 GMT

@Dan_the_Van

I am powering my ONT via an APC UPS. To connect it I had to use the supplied 2.5/2.1mm pin adapters to interface the APC 2.5 mm pin connectors to be compatible with the 2.1mm pin/socket size used by the ONT and its PSU.

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Wed, 26 Mar 2025 09:34:07 GMT

Thanks to everyone who has posted

@outcast

The TP-Link PoE would be a bit over the top for 3 metres, I did look for a reference paper by openreach on the specifications for a ONT but I failed, your attachment was what I was looking for.

Now have it confirmed the size by the attachment and @Baldrick1 I can proceed with planning what I like to have done.

Re: ONT extension DC power cable and Fibre cable used

bmc — Thu, 27 Mar 2025 17:23:17 GMT

@Dan_the_Van

I see from another post today that FF is now on order.

I would repeat my sugggestion that no work is done until you've spoken to the engineer on the day and agree the access point. If trunking is required you should be able to fit it quickly while the outside work is done.

Do let us know how it goes on the day.

Brian

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Thu, 27 Mar 2025 17:50:21 GMT

@bmc

I've now come to the conclusion to have the ONT installed to an outside wall in the cupboard.

I will use a 12v dc extension lead and a 4 metre length of cat 6 utp between the router and ONT, the cables purchased are flexible so no worry of damaging the fibre core.

The redundant Openreach Master Socket will be converted to a power socket.

So my only worry now is the 90 degree turn on the outside wall, I've got until 15th April to work out what might be needed, if anything.

Not sure why I'm overthinking this, I've planned and installed far more important projects than this.

Thanks again for taking an interest.

Re: ONT extension DC power cable and Fibre cable used

shutter — Fri, 28 Mar 2025 14:39:17 GMT

@Dan_the_Van

Right angle corner problem.........

see the pic !

You could leave the loop "free floating" ..or you could fix a wooden block ( say 2" x 2" ) to the corner and secure the cable down on the top ( or below ) .

The above pic is a "mock up" not "reality" ! ...

Re: ONT extension DC power cable and Fibre cable used

RobPN — Fri, 28 Mar 2025 15:51:48 GMT

IMO, a somewhat ridiculous suggestion for an outside cable which I'm sure an OR installer would go for - NOT!

I'm surprised nobody has suggested the following, quickly mocked up using a bit of old 4" x 4" timber etc. in my back yard.

Could also be used where two walls meet forming internal angles.

(Or if the outside wall is brickwork, the mortar bed could be chased out to accommodate the cable thickness and curve required.)

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Fri, 28 Mar 2025 16:19:20 GMT

@shutter

Thanks, in the past I have had to use various methods for running cables in the strangest of places, the most interesting was at the top of a mast of the Esso York Oil Tanker many years ago.

I appearing to be suffering from QRM so I'll wait until it goes away!

Re: ONT extension DC power cable and Fibre cable used

Dan_the_Van — Tue, 15 Apr 2025 12:56:34 GMT

So to end this thread with a fix for me 🙂

I bought

CDL Micro 5m DC Jack 5.5mm x 2.1mm Power Male to Female M-F Extension Cable for CCTV

Reulin Ultra-Thin, Ethernet Cable, 4M-Black, High-Speed Internet Lan Wire Cat6

11 x 11 mm cable trunking.

The Fibre cable came to the house direct from the chamber adjacent to my property to the CSP then to the ONT.

After checking the cable run it appears the Openreach engineer chased out a very small amount of cement from the corner brickwork, no more than was required to allow for the turning circle. I think some mentioned doing that but I don't recall who.

ONT, the trunking runs on top of the skirting board up the side of the door frame to the shelf above the door, where the router lives with my two NAS drives and VPN servers.

So I now have a 150 / 30 connection compared to 72 / 15

We decided to drop the landline service.

Re: ONT extension DC power cable and Fibre cable used

RobPN — Tue, 15 Apr 2025 14:17:17 GMT

@Dan_the_Van wrote:

After checking the cable run it appears the Openreach engineer chased out a very small amount of cement from the corner brickwork, no more than was required to allow for the turning circle. I think some mentioned doing that but I don't recall who.

That'd be your so-called QRM.

Re: ONT extension DC power cable and Fibre cable used

spile — Wed, 16 Apr 2025 05:26:34 GMT

I am finding this is a fascinating thread. I think I need to get out more.