Why won't this phone extension work??

[PC Electrics]

Installed a phone extension today. Usually these things are easy enough. Just connect the coloured wires to the correct number terminals and off you go.

However, today I could get no response from the new extension socket. So I went back to the parent socket, which afaik is the master. Plugged in the phone - nothing, no dial tone, nothing.

I tested the new wiring, continuity ok and no shorts.

With the extension wiring disconnected from the master, the phone worked fine. After some more faffing, I discover that even with the extension wiring disconnected at the other end, as soon as I connect any wire into terminal 5 of the master, the line goes off - dead.

Complete madness!

The extension cable passes through the loft and has a total length of about 30 to 35m. For some of it's length it takes the same route as some network cables. Don't know if that's relevant info or not.

The master socket is BT branded (also has PCS on it) and is pictured below from behind.

Can the amassed brain power of the forum come up with any answers?

 

[Theorysparky]

Is it a master socket that has 2 parts ???

one part has the incoming A-B the other part has the extension part ???

try a new master socket and slave

and are you sure there are no other slaves in the house ???

 

[kerching]

does not look like a master socket to me ! A master should have 3 components in it

opt out of service resistor

bell cap

surge arrestor

you .I think, have a PBX or APBX socket...try another master socket [bearing in mind that faffing with the Master is restricted to BT or their minions, you have been warned]

I may well be wrong, see wife for details............. :coat

---------- Post Auto-Merged at 21:44 ---------- Previous post was made at 21:40 ----------

does not look like a master socket to me ! A master should have 3 components in itopt out of service resistor

bell cap

surge arrestor

you .I think, have a PBX or APBX socket...try another master socket [bearing in mind that faffing with the Master is restricted to BT or their minions, you have been warned]

I may well be wrong, see wife for details............. :coat

just noticed the big give away it has LJ2/2A on it. that is a PBX master

 

[Theorysparky]

Respect big man

didnt notice it

eyes wide shut (would have fixed when i swapped it over !!!)

 

[PC Electrics]

just noticed the big give away it has LJ2/2A on it. that is a PBX master

so,what does that mean? What should I do about it?

 

[Theorysparky]

PC

Get yourself a master socket

replace the BT one temporarly test for dial tone at the extension and make calls in and out

when you are happy that your stuff works put BT one back in and phone them while the customer is there

is BT the provider of the phone line ??? or has the customer got a sky package ???? if its sky then phone them,,,,,,,,

let us know

 

[NozSpark]

TBH I'd just swap the master and then if it still had a problem on connection of the extension then I'd make a temporary hard wired extension.

Long shot ------- Maybe the existing extension cable is wrapped around a heating pipe somewhere and it's shorting to earth?

 

[IzzyS]

The lack of surge arrestor shouldn't in itself cause it to not work. Just not arrest surges. Obviously they're not required on a PBX as all the cabling is (usually) indoors and unlikely to be struck by lightning.

Have you done an IR test (250V) on the cabling to the slave?

 

[Theorysparky]

PC

Did you get this fixed ???

 

[batty]

How can he answer that it still broke.

 

[PC Electrics]

No Theo. The property is 35 miles away, so I'm not just going to go on a whim. If I had a positive reason and a solution I'd go, but I haven't.

---------- Post Auto-Merged at 16:16 ---------- Previous post was made at 16:12 ----------

Is it a master socket that has 2 parts ???one part has the incoming A-B the other part has the extension part ???

try a new master socket and slave

and are you sure there are no other slaves in the house ???

There are loads of other extension sockets in the house.

 

[Theorysparky]

its not down towards me is it

northants way ?

 

[Jono Pashley]

No Theo. The property is 35 miles away, so I'm not just going to go on a whim. If I had a positive reason and a solution I'd go, but I haven't.---------- Post Auto-Merged at 16:16 ---------- Previous post was made at 16:12 ----------

There are loads of other extension sockets in the house.

This may be complete and utter rubbish but im sure ive seen somewhere that only a certain number of devices should be run off a single master socket.

 

[Sidewinder]

Jono,

You are correct the REN sum of connected devices must not exceed 4.0.

Well it USED to be the case.

 

[PC Electrics]

Yes Theo, just off J11 of the A14, SE of Kettering

 

[kerching]

Yep, REN [ringing equivalence number]

Total not to be greater than 4.

REN number is written on each device, usually it is 1. but some foreign sh!te is in excess of 1.......... :coat

 

[timgdean]

Ok then my bit..

Is the socket a 'line box' (split in half )otherwise known as a nte5 ?

If yes then try a phone in the back of the cover plate.

Then check your wiring is connected to the front piece. 1-1 2-2 ect

Often it is problems like snapped wire.

Doing an Ir test down the phone line can blow the fuses at the exchange..

T.

 

[Steve3948]

This may not be the master, as the incoming would only be 2 wire connected to 2&5 or A&B, so whey is the green connected indicating it's a ringer connection.

You can have more than 1 master on an installation but you do not need connection 3 as the capacitor rings the phone.

A few years ago I was told to put masters on all sockets by BT and wire them in star format all back to a junction, it was right out in the middle of nowhere though so I suspected voltage issue in ringing more than one phone.

I does sound like a short in the secondary wiring though.