BT telephone wiring, colour codes, common faults & cable quality
April 28th, 2016 11:54 am

In this post we cover some common BT wiring faults/mistakes, colour code schemes & why cable quality with broadband is VERY important! We also explain the bell wire & why you really want to have the latest NTE5 and most probably a SSFP too (what on earth is an SSFP you ask?! Well read on to find out!!......

Some common faults

Phone ringing continuously
Terminals 2 and 5 swapped between sockets (2 at one socket connected to 5 on another and vice versa)
No ringing
Terminal 3 disconnected

Ringing but no speech (or very poor speech) and can't dial out.
Wire between terminals 2 or 5  broken.

Very poor speech quality, possibly poor bell
Terminal 3 and 2 or 3 and 5 transposed

Colour Codes

BT Openreach are using new cables with new colour codes. The old wiring scheme was as follows :-

Connector 2 - Blue with White Rings
Connector 3 - Orange with White Rings
Connector 5 - White with Blue Rings

This has now changed to :-

Connector 2 - Blue
Conector 3 - Brown
Connector 5 - Orange

The ring wire or bell wire

You have most probably heard of the "ring wire" or "bell wire" & why it is bad news for ADSL & vDSL broadband. Removing the bell wire (pin 3 on the IDC block of the MASTER socket, eg, NTE5) can certainly improve ADSL/vDSL performance if you have internal extension wiring (if you don't have any extension wiring then you shouldn't have a bell wire!). However removing the bell wire is against the BT wiring specification. So what can you do? Well, the good news is BT along with their suppliers cured this problem with the addition of a bell wire filter (or inductor to use the correct term) which is fitted to the latest BT NTE5A socket (which we sell!). In short the addition of a 22mH choke on the circuit effectivily removes the bell wire from the equation while leaving it in place to do what it is there to do!!

So what's the issue? Read on.....

The problem arrises when internal wiri...

BT Openreach External NTE (XNTE)
April 28th, 2016 11:49 am

BT Openreach will discontinue the use of the XNTE when current stocks are exhausted. This is due to the fact that vDSL services require a SSFP (Service Specific Face Plate) which in turn NTE5 socket!! We saw this coming from day 1!! If you have an XNTE and upgrade to vDSL then the Openreach engineer will gel crimp your internal wiring directly to the BT pair outside. The XNTE will become nothing more than a junction box, a new NTE5 will be fitted along with the vDSL faceplate as pictured below (the vDSL extension connections are circled in RED).


We first reported on the XNTE back in September 2009......

Openreach have started to fit external NTE's in place of the popular NTE5 socket. The only real benefit is to Openreach themselves as the new socket means they can easily disconnect any internal wiring & diagnose line faults without requiring entry to the premises. However, if you have ADSL then you should consider changing the first socket on any internal wiring so...

NTE5A Design Changes
April 28th, 2016 11:42 am

The NTE5A has been revised a number of times during production, most notably :-

Product Change Announcement - 07/11/2008

Products concerned –
BT style NTE 5A – All variants
BT style NTE 5B – All variants

Scope of Change –

1) The NTE5 CCU (customer connection unit) currently incorporates a 4 way IDC connector. It is intended to change this to a 3 way IDC connector which will allow connections to pins 2, 3 and 5 for the line and ringing circuit. Note ; where 4 wire extension cabling is used, continue to use the same conductor colours relevant to terminals 2,3 and 5 and leave the conductor normally terminated to pin 4 unconnected.
2) On certain variants of NTE 5A and 5B, the design allows drop wires to be attached to two metal terminal posts via a screw and captive washer. It is the intention to replace these terminal posts with a 2 way IDC connector.
3) Currently most variants of NTE5 incorporate a Bell Wire Filter, it is the intention to make this a standard fitting on all var...

How to install a VDSL extension
April 28th, 2016 11:35 am

At present BT install the Openreach VDSL modem at the master socket location and will run a data cable to the router in a separate location if required. However, the VDSL faceplate does have provision for a hard wired VDSL extension.....


For telephone & VDSL at the remote location :-

(1) Terminate cable for phone to 2, 3 & 5 on the lower front faceplate (the original NTE5 part)
(2) Terminate another pair to the two IDC connections on the VDSL faceplate
(3) Terminate 2, 3 & 5 to a BT Euro Module (
(4) Terminate the pair from the VDSL plate to an RJ11 Euro Module (, the modules snap into a Euro double faceplate ( Terminate to pins 3 & 4 as marked on the RJ11 module PCB (if using an RJ45 module - - pins 4 & 5...