What Color Are The Voice Phone Wires That Enter The House

Wiring modern phone sockets (Line Jacks)

Wiring Diagram for Principal & Extension Telephone Sockets

Wiring diagram

Pin	Use	Master Socket	1st Secondary Socket	2nd Secondary Socket	3rd Secondary Socket etc.	Pin
1	Not used§	Dark-green/White	Light-green/White	Green/White	Green/White	one
2	'B' wire (-50V to earth)	Blue/White	Blueish/White	Blue/White	Blue/White	ii
3	Bong wire	Orangish/White	Orangish/White	Orange/White	Orange/White	3
4	Earth (PABX use merely)	White/Orange	White/Orange	White/Orange	White/Orangish	4
5	'A' wire (0V to world)	White/Blueish	White/Blueish	White/Blue	White/Blue	five
half-dozen	Non used§	White/Green	White/Green	White/Light-green	White/Green	6

When 'new-mode' wiring was introduced in the early on eighties a domestic single line telephone installation would have a master socket which is provided by the service provider (B.T., cable visitor etc.). This was usually an LJU2/1A or a LJU3/1A blazon of socket. A master socket contains a i.8µF capacitor to laissez passer ringing current to the telephones, a surge arrestor 11A or 26A to suppress high voltage spikes etc. and a 470k ohm resistor for testing purposes. Boosted secondary sockets are wired off the master as shown above, the color codes shown are the standard, but may differ in some existing installations. The wiring diagram for a master LJU socket is shown here. Note that the pictorial view shown higher up only serves to indicate the two differing types of sockets and wiring connections. Reverse to how it might seem, C1 is connected to terminals 2 & iii, not 1 & iv

NTE5 Line-box wiring instructions

In more recent years NTE5 or CTE5 Lineboxes are fitted in place of master sockets, these have a removable (lower half) panel which house the terminals to connect wiring to the secondary sockets. § Terminal pins 1 and 6 may be absent on some versions of C/NTE5, but these connections are not unremarkably used anyhow. The NTE5 tends to take the same components inside as a master LJU, however later NTE5 sockets differ by not having a surge arrestor, have only pins two, 3, 4 & v or two, 3 & v connected, they besides have a small ringlet in serial with the 'bell wire' on pin 3 which acts as a filter.

On older installations (pre-1980) cream or grayness cables were used. They contained conductors coloured bluish to pin 2, orange to pin 5, brown to pivot iii and green to pin 4 (if used), on some conversions green was used for pivot 3 and brown for pivot 4. On some installations of internal extension wiring (mail service-2012) BT/Openreach have at present come full circle and have reverted back to using white four cadre cablevision containing solid colours: blueish to pin 2, orangish to pivot 5, dark-brown to pin 3 and light-green to pin 4 (if used).

Additional Bells are wired between pin iii (orange/white) and pivot five (white/blue).

External overhead phone line color code: orangish / white = line 1; light-green / black = line 2.

Wiring Faults

Telephone line dead or similar issues

NTE5 Test Socket

Almost homes with a landline volition have a master socket called an NTE5A, this socket has a concealed test socket in which you can plug in a phone to exam the line.

To expose the test socket simply remove the two screws and gently pull off the front faceplate, be sure to do this gently every bit at that place may be wires connected to the back of it.

You lot will then see the test socket in which y'all can plug in a phone in lodge to exam the line. If the line now works then it is very likely that you accept a fault with your extension wiring or sockets. If the line is still dead and then the likelihood is that the fault is exterior your domicile, although it could all the same be a mistake on your property.

The latest blazon of principal phone socket is called an NTE5C, the aforementioned principal applies except that the front faceplate simply unclips from each side, rather than beingness screwed on.

Phone ringing continuously:

No ringing:

Ringing simply no speech (or very poor spoken communication) and tin't dial out:

Very poor spoken language quality, possibly poor bell:

Terminals 2 &5 swapped between sockets (2 at i socket continued to five on another & vice versa)

Terminal 3 disconnected

Wire broken betwixt terminals 2 or 5

Terminal three and two or 3 and 5 transposed

Telephone Cablevision Wiring Colours

CW1311 Internal four/six Fashion Telephone Cordage

Contact ane	Black	organisation phones	half-dozen-manner just
Contact 2	White	'A' wire	4 & 6-manner
Contact 3	Green	Earth wire	iv & 6-mode
Contact 4	Blueish	Bell wire	4 & 6-manner
Contact 5	Red	'B' wire	4 & 6-way
Contact 6	Orange	system phones	6-way only

CW1308 Internal Phone Cable

Pair No.	'A' wire	'B' wire
1	White/Blueish	Blue/White
two	White/Orange	Orange/White
3	White/Greenish	Light-green/White
4	White/Brown	Chocolate-brown/White
v	White/Gray	Gray/White
half-dozen	Blood-red/Blue	Blue/Blood-red
7	Red/Orangish	Orange/Cherry
8	Red/Greenish	Green/Ruby-red
9	Blood-red/Brown	Brown/Carmine
ten	Red/Grey	Grey/Red
eleven	Blackness/Bluish	Blue/Black
12	Black/Orange	Orange/Black
13	Black/Green	Light-green/Black
14	Blackness/Chocolate-brown	Brown/Black
15	Blackness/Gray	Grey/Black
16	Yellowish/Blue	Blue/Yellowish
17	Yellow/Orange	Orange/Yellow
18	Yellow/Greenish	Light-green/Xanthous
19	Yellow/Brown	Brown/Yellow
20	Yellow/Gray	Greyness/Yellow
21	Violet/Blueish	Blueish/Violet
22	Violet/Orangish	Orangish/Violet
23	Violet/Light-green	Light-green/Violet
24	Violet/Brown	Chocolate-brown/Violet
25	Violet/Grey	Grey/Violet
26	Pink/Blue	Blue/Pinkish
27	Pink/Orangish	Orange/Pink
28	Pinkish/Dark-green	Green/Pink
29	Pink/Dark-brown	Brown/Pink
30	Pink/Greyness	Grey/Pink

CW1293 Internal Telephone Cablevision

Pair No.	'A' wire	'B' wire
1	White	Bluish
two	White	Orangish
iii	White	Green
4	White	Chocolate-brown
5	White	Grey
vi	Reddish	Blue
7	Cherry-red	Orangish
8	Crimson	Green
9	Red	Chocolate-brown
10	Cherry	Gray
11	Blackness	Blueish
12	Blackness	Orange
13	Black	Green
fourteen	Black	Brown
15	Black	Greyness
16	Xanthous	Blue
17	Yellow	Orangish
18	Yellowish	Green
19	Xanthous	Brownish
twenty	Xanthous	Greyness
21	White/Blueish	Blue
22	White/Blue	Orange
23	White/Blue	Green
24	White/Blueish	Brown
25	White/Blue	Grey
26	Cherry/Bluish	Blue
27	Ruddy/Blue	Orange
28	Carmine/Blue	Green
29	Cherry-red/Blueish	Chocolate-brown
30	Reddish/Blue	Gray

CW1128 & CW1326 External Cable

Pair No.	'A' wire	'B' wire
1	White	Blue
two	White	Orange
3	White	Light-green
4	White	Brown
5	White	Grayness
vi	Red	Blue
vii	Reddish	Orangish
8	Cherry	Greenish
ix	Red	Brown
x	Carmine	Grey
11	Black	Blueish
12	Black	Orange
13	Black	Greenish
14	Blackness	Chocolate-brown
15	Black	Grey
sixteen	Yellowish	Blueish
17	Yellowish	Orange
18	Yellow	Dark-green
xix	Yellow	Brown
20	Yellow	Grey

CW1406, CW1411 & CW1417 External Dropwire Cable

CW1406	CW1378 & CW1411	CW1417 (CAD55M)
1-Pair No.12	ii-Pair No.10/10B	4-Pair No.14	'A' wire	'B' wire
1st pair	1st pair	1st pair	White	Orangish
n/u	north/u	2nd pair	Grey (slate)	Ruby-red
n/u	north/u	3rd pair	Brownish	Blue
n/u	2nd pair	fourth pair	Blackness	Green
Dropwire comes in 1-pair, 2-pairs or 4-pairs, the cable besides has three steel tension wires to give support.

CW1406, CW1411 & CW1417 External Dropwire Cable

Pair No.	'A' wire	'B' wire
one	White	Orange
2	Black	Greenish
Double sheathed external course telephone cable bachelor in white & brick dark-brown colours.
Item code: 055354

Early on blazon of external dropwire cable were constructed of one parallel pair in a figure-8 configuration.

BT dropwire reference	No. ane	No. 2	No. vi	No. viii
CW Reference	CW1166	CW1208	CW1247	CW1320A
Conductor Type	Solid cadmium copper	Solid copper covered steel	Solid copper covered steel	Solid cadmium copper
Nominal Conductor Bore (mm)	0.91	0.71	0.81	i.14
Conductor Size (mm²⁾	0.65	0.four	0.52	1.02
Minimum Insulation Resistance @500V DC (MΩ.km)	24	24	50	24
Minimum Insulation Thickness (mm)	0.75	1.02	0.8	one.52
Nominal Insulated Conductor Bore (mm)	2.41	ii.75	2.41	4.18

Colours for CW1109 Jumper Cablevision used on Master Distribution Frames (MDF) inside BT Telephone Exchanges

Application	'A' wire	'B' wire
TXE4 & misc. not PSTN BT circuits	Blue	Yellow
Organisation 10 circuits	Dark-green	Black/white
Organisation Y (AXE10)	Orange	Turquoise
Individual circuits	Pinkish	Gray
Featurenet & Redcare circuits	Red	Yellow
DACS & WB900 Circuits	Greenish	Yellow
P wire busying	Green	–

Jumper wire colours

CW1109 Jumper wire is available in diverse colours, including, ruby/white, ruby/black, blue/yellow, blue/white, green/white, green/black and pinkish/gray. It is used for connecting MDF's and for Krone disconnection strips.

Note regarding telephone cable colours

When describing phone wiring the color grey is often referred to every bit slate. This is to avoid whatever confusion between green and grey as the first three letters are both the same.