I’ve noticed that the query “How To Wire a Master Socket” crops up frequently on Google.
We’ve blogged on this topic in recent times, so it might be worth taking a look here,too.
As a telephone engineer, it would pay me to make things very complex and difficult for readers, and make it clear that this is a job for “the professionals”. Don’t worry – I won’t.
However, I need to make it clear that strictly, the master socket is property of Openreach. I have blogged on this topic here and here. In theory, no-one should touch it. Meanwhile, in reality…………………. (hello??)…..
Before I Start (Tools, Cable and Voltage)
You will need a proper cable insertion “punch-down” tool to push down cables onto terminals. These are available on eBay/Amazon – (search for Krone Tool, insertion tool). Don’t use a screwdriver blade – you will damage the connectors! I have blogged on cable and jointing here and here. Hazardous current? Measured in Milliamps. Only enough to give you an occasional “tickle”.
Down from a Pole, or Up From a Hole. What Goes in The Back?
This is how your telephone/broadband service arrives on your property, via a single pair of wires, each containing half a millimetre diameter of copper. Amazing. I’m surprised it ever works as well as it does. These need to go on the back of your socket.
Exactly “Where” On The Back?
On the very back face on your master socket are two terminals marked “A” and “B”. The wire goes here. It doesn’t matter in which order. Old-style sockets have screw connectors. Later ones have punch-down or plastic-lever-type connectors.
Help! So Many Colours….
(Don’t worry – it’s fairly logical.)
Colours:- from an underground cable. These are “paired” as “plain blue-plain white”, “plain orange-plain white”, “plain green-plain white”, “plain brown-plain white”, “plain grey-plain white”. It is probable that your service is on the “blue” or “orange” pair. Important – the corresponding white wires can only be identified by whatever colour they are twisted around. Therefore, take care in unbundling them. However, fear not – if you mix them up, simply swap the white ones around until you hear a dial tone. Much more on underground cable here.
Colours:- from a pole. Orange and white (normally used first), then green and black. More on “drop wire” here.
What Goes On The Front?
By “front”, I mean the detachable bit of your master socket, usually the bottom half, but occasionally the whole front on newer ones.
Here you will see some punch-down terminals numbered “2”, “3”, “4”, and “5”. In most cases, you only need to add any extension required to “2” and “5”. Use the “blue/white”- “white/blue” pair of cables for the sake of convention.
Wait a Minute! – There’s a Couple of Terminals Marked “A” and “B” On The Front.
Yes indeed. On some newer sockets, you’ll find these. They provide a filtered broadband output. Use high-quality cable (such as Cat 5 or Cat 6 data cable)to where you want your internet router to be, and you are making the very best use of your broadband. More on this here.
That’s about it. Very occasionally, your cable from outside will be jointed before it gets to your master socket. Normally you can find a connecting box where the transition from the exterior cables to the interior ones is made. The convention is to use the “blue/white”-”white/blue”. Very occasionally, with either very old or very new cabling, a “blue/orange” pair will be used.
It’s Not Hard!
Trust me, it’s simple if you take your time and don’t panic. You can’t break anything. There won’t be a call from The Socket Police. If the exchange building catches fire, you won’t have caused it.
However, we do not suggest that you interfere with Openreach’s property.
Meanwhile, if you need help and are local, give me a call. If you are not local, drop me a line with your postcode, as I am in touch with independent engineers throughout the UK.
However, I can’t run a free help desk, so all I’d ask is that of this “How To Wire A Master Socket” guide has been helpful to you, you leave a very short review on Facebook or Google. Thanks.
Thanks for this wealth of info, I’m learning lots!
Currently with Sky on their ‘superfast’ FTTC. Running a check on some providers websites says I should get up to 51 mbps but I’m currently getting around 36 mbps so I thought changing the old master socket for a NTE5C Mk4 might help increase the speed a bit. Just swapped it over and so far no improvement. Does it take a while to stablise? I have seen reports that seem to indicate it’s an instant improvement if it’s going to happen.
My phone line comes across the street from a pole which is received on the front of the house where there is a 6 inch (ish) black cylinder which I assume is splitting the wire two ways – one goes to a bedroom upstairs (the socket is no longer there) and the other to the downstairs where my master socket terminates. Am I potentially losing speed because of the splitter outside?
I thought installing a new line might help but reading up I believe they would just use the spare pair of wires on the existing cable so that wouldn’t help – would that be right?
Is there anything else I’m missing?
Thanks for your help
Dave
Thanks for this wealth of info, I’m learning lots!
>Thank-you!
Currently with Sky on their ‘superfast’ FTTC. Running a check on some providers websites says I should get up to 51 mbps but I’m currently getting around 36 mbps so I thought changing the old master socket for a NTE5C Mk4 might help increase the speed a bit. Just swapped it over and so far no improvement. Does it take a while to stablise? I have seen reports that seem to indicate it’s an instant improvement if it’s going to happen.
>Both can apply. You could try a power on/off with your router. Broadband speed can be a mysterious thing. What do Sky guarantee? If it falls short, get in touch and press for action!
My phone line comes across the street from a pole which is received on the front of the house where there is a 6 inch (ish) black cylinder which I assume is splitting the wire two ways – one goes to a bedroom upstairs (the socket is no longer there) and the other to the downstairs where my master socket terminates. Am I potentially losing speed because of the splitter outside?
>The “splitter” may simply be the enclosure for two pairs of wires. Was the line to the bedroom once a separate exchange line? Or is there a possibility that someone has tee-d into the incoming line upstream of the master socket, and this is now attracting interference?
I thought installing a new line might help but reading up I believe they would just use the spare pair of wires on the existing cable so that wouldn’t help – would that be right?
>Yes
Is there anything else I’m missing?
>An independent engineer might be able to spot something else.
Thanks for your help
>You’re welcome.
Dave
Cheers Rob all really helpful.
When you say it may be attracting interference, is there anything I can do to check this? Or is an independent engineer needed?
D
Hello,
Not really, apart from opening the box on the outside of the house. It is unlikely that someone has tee’d into it, but with domestic wiring, subject to the wiles and behaviour of amateurs, anything can happen!
If you want to have a rummage via Google, there are pages which describe how to use a medium wave-tuned radio to trace interference, if you wanted to get really “obsessive-techie” Here’s one:-
https://kitz.co.uk/adsl/rein.htm
My suggestion is to persevere with your provider if their service is below the guaranteed speed.
The cynical, “almost-sixty” engineer in me, aware of what exists in homes, up poles, down holes, and is exposed to poorly-skilled engineers, is amazed that broadband ever works at all! 🙂
Rob
HI,
Is it possible to run two master boxes from the one incoming cable splitting them at the incoming junction box.
Thanks
Hamish
I’m a bit puzzled – why would you want to do this? A master socket usually serves a secondary socket, usually giving a phone service to somewhere elase in the property. I have also blogged extensively on how to connect your router to a master socket. Can you give more details, please?
Hi,
I understand what you are instructing. The
master socket is at one end of the house and the incoming junction box is at the other end where i plan to install the router. Not easy access between the two.
Thanks
Hamish.
There’s plenty on our blogs about getting your master socket where you need it to be. I’ve created an index here:-
https://telecomgreen.co.uk/home-phone-repair/an-index-of-telecomms-help-moving-a-master-socket-and-other-stuff/