This topic

What are these BT boxes ?

edwardskevin — Tue, 08 Sep 2026 16:12:47 GMT

Hi Team

I am moving into a 8 year old house that part of which was previously used as an office and BT supplied the internet .

The internet connection boxes (untidily installed in cupboard under stairs)

I am changing internet provider (probably to 900gb fibre from Sky) . No phone requirement .

Regarding the three BT equipment boxes shown in the picture , I understand the modem (will be removed) and the ONT (fibre terminal with the lights , which has to stay ? can be switched off ?) .

But what is the rectangular BT business box function and can it be removed ?

Value your comments 👌

Re: What are these BT boxes ?

imjolly — Tue, 08 Sep 2026 16:21:27 GMT

The 'boxes' are the property of openreach not BT RETAIL so I would talk to your SKY installer

Re: What are these BT boxes ?

edwardskevin — Tue, 08 Sep 2026 16:31:00 GMT

ok, but what is the function of the rectangular box above the ONT box ?

Re: What are these BT boxes ?

iniltous — Tue, 08 Sep 2026 16:44:04 GMT

The rectangular box above the ONT , is the PSU (power supply unit ) for the BBU (battery back up unit ) as this is clearly a PSU as its plugged into a mains power outlet, I’m not sure you have identified the ONT correctly .

The box to the right of the mains sockets and Ethernet patch panel, which I think you are incorrectly identifying as the ONT is the CSP (customer service point )

Re: What are these BT boxes ?

iniltous — Tue, 08 Sep 2026 16:56:08 GMT

On closer inspection you probably think the BBU is the ONT because the lead from the PSU is labelled as ONT , in this old style FTTP installation, the power lead goes to the BBU which powers the ONT , the power lead can also be connected directly to the ONT leaving the BBU out if the ‘chain’ , which in this case would make no difference as it’s in an alarm state because its batteries are now defective so in a mains power failure it would not power the ONT anyway .

Re: What are these BT boxes ?

edwardskevin — Tue, 08 Sep 2026 21:34:24 GMT

Many thanks everyone ,, much appreciated

If I have this correct then It seems that I have :

# a Huawei EchoLife 4 port ONT (will only need replacing by the ISP for speeds exceeding 1 Gbps)

# a now obsolete Battery Back Up (BBU) which can be disconnected with the psu going direct to the ONT . (only previously used for Voice Telephone backup )

# an internal Customer Service Point (CSP) , where the incoming fibre cable ends and a fibre patch cable takes over connected to the ONT

Thanks all 👌