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Master socket front plate question

Posts: 1
Registered: ‎18-11-2019

Master socket front plate question

Hi - I'm looking to replace the front plate which is part of an old BT box.

At the moment there are lots of wires connected to the plate, but I have no idea what they are for.

Do I have to connect the wires onto a new front plate?

Also any ideas where I can find a replacement from? I don't want to have to replace the entire box!


Many Thanks



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Registered: ‎01-08-2007

Re: Master socket front plate question

It looks as if there is one extension wired into the front plate - the white/blue and blue/white pair. If you want that extension to continue to work you will need to connect those wires into any new front plate you install.

The white/red and red/white pair do not appear to be connected and so you should not connect those to any new front plate.

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Registered: ‎30-06-2016

Re: Master socket front plate question


I would suggest that you fit a filtered faceplate such as one of these.

After fitting it you no longer need to use micro filters. If you want to use the extension then the pair of blue/white cables only should be connected. The terminals to use will be identified on the instructions that come with the filtered faceplate..

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Re: Master socket front plate question

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Re: Master socket front plate question

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Re: Master socket front plate question

Moderator's note(s):

Thread moved from Home Phone to Tech Help.

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Registered: ‎17-07-2016

Re: Master socket front plate question

The white/blue & blue/white pair are an extension or extensions from the BT master socket.

I also strongly recommend a filtered faceplate and connecting your router to that.

The white/orange and orange/white can be a bell wire and (generally not used) earth. If extensions ring you either have a socket elesewhere with the required capacitor or relatively modern phones that don’t need a primary socket.

All in all, if it works at present leave the wiring as is.

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