Old BT phone incoming wiring check

bill_fortan

Hello, I have an old BT incoming joint box. that wires to the old master socket box. (circ 1965)
I want to upgrade to the new type (master phone box with built in phone test socket).

A 2018 BT Openreach Kauden telephone master socket NTE5A. I have ordered one from Ebay.

Question..the old three wires coming in the joint box is Blue, orange and green..
Can you please confirm that the following is correct....
blue is -50V
orange is 0v
green is the 'ring' sound

The reason I say this is....
blue goes to terminal 2 in the old master socket box
orange goes to terminal 5 in the old master socket box
green goes to terminal 3 in the old master socket box

Thanks, I just want to make sure I have it right, before i connect up to the new master socket. Cheers Bill.

iniltous

The external wiring from the DP ( distribution point ) is only 2 wires, not 3, the third wire must be from a point where the external cable has effectively been converted into 'internal' wiring .
The third wire isn't necessary anymore , called the bell wire , it was used to suppress 'bell tinkle' on rotary dial phones, and these days , left connected messes up broadband , so you only need the 2 wires from 'outside' , connected to the A and B terminals of the master socket.

AndyPK

pictures always help.

You could get fibre installed and they would prob do this for free!

The 3rd wire could be a ground wire. Used for a short period.
or it could be a ringer wire for another extension? You say its connected to 3 in a plug/socket so must be ringer for another extension. Connect to 3 if you want the extension to ring

The new box will have terminals marked A and B where the external wires should connect in the top half.

B is the same as 2
A is the same as 5

Mister_G

Strictly speaking a Master Socket should only be installed by Openreach, as it is the termination point of their line into your property.

If you do not have a Master Socket, you should be able to get your CP to get OR to provide one.

bill_fortan

Thank you for your quick responses. I did not know a an b terminal so thanks for that.
Yes third wire (green) does allow other phone extension upstairs to ring.

The main reason for getting new master socket is that the old master socket is located under under the hall radiator on the skirting (water filled radiator/gas central heating), and telephones have been acting up with crackling over the past two years, so going to change it. for the new master socket, and move it away from radiator. Plus it gives me instant check on line with the built in test socket on the new master socket.

Just wondering if the capacitor in old master socket has been drying up and causing problems? as old master socket its circ 1965, but radiator was placed just above it by last owner in 2002..Anyway moving it is the answer. Do not like it under a radiator.

AndyPK

I'm sure bt only invested the rectangular socket in the 1980s

Previously lucky people had round large headphone like plugs.

AndyPK

Is your router plugged in upstairs?

bill_fortan

I only moved into the house in 2002 so likely the rectangular connection box was put into my living room in the 80's then, I have no idea. . But the cable then runs from connector in the living room to the hall where there is the old master socket under the radiator (downstairs telephone there in hall), then one extension socket upstairs for another telephone and router.

Router is upstairs, no problems with it.

bill_fortan

Ok, new 2018 master socket installed, a half hour job, now moved location to the right of the radiator, and many thanks to you guys for your help.

At least now I have that test socket on new master socket, the next time I have line problems, which unfortunately happens a lot in my street when a BT Open reach guy goes into the manhole on the pavement outside my house, to fix one houses line and upsets others, as its old wiring.

So much for the fiber optic age LOL.

PS..you were right guys, the green incoming wire at the joint box was not used, and was just cut off in the old master socket, so it was two wires in.

AndyPK

Test sockets aren't that exciting!


Only any point if other extensions are connected to the bottom flap on the master socket. Thus they get isolated when bottom removed to expose test socket