Advice on re-wiring / installing phone main socket connection

flywheel

Hi, trying to locate the phone line in an apartment and found this under a blanking plate (only camera phone to hand sorry!)... no other sign of a phone line anywhere so assuming this is it?



Trying to work out from the wires is:
L1 (R1): Blue (White)
L2 (T1): White/Blue

So do i need to wire L1 and L2 to a NTU and then see if it is still connected to the exchange?

thanks

Solair

Ireland uses a 2-wire phone system, it's actually very simple.

The line will either be on the orange pair, or the blue pair. Simply connect it up to any RJ11 (normal) telephone socket and you should get a dial tone.

Technically speaking, you should have an eircom NTU, but in reality an eircom NTU socket isn't really anything more than a normal phone socket with an ability to isolate your internal wiring from their network should you need to test the line.

Most installations pre 2001 don't have any NTU, just standard eircom sockets.

There are no complications in the Irish system like 'master sockets' and 'slave sockets' as there are in the UK. That system was abandoned a long time ago. So, just find out which pair the line is on and wire it to your phone sockets and you should be fine. However, the eircom branded sockets do contain a capacitor, much like their british cousins. This was used for backwards compatibility with some old hard-wired installations where old style 3-wire bell ringer telephones were used. No modern (post 1970s) installation in Ireland uses that.

The only thing I would say is do not use a BT master socket (e.g. from maplins or B&Q) this may add all sorts of complications that you don't need!

The only bit of advise is use good quality accessories i.e. use CAT5 cable internally for better shielding and don't run too many extensions if you're using DSL.

In general long runs of flat (non twisted pair) cable will degrade DSL signals as the cable can behave like a radio antenna picking up all sorts of noise that can mess up your DSL.

US wiring colours apply here so use the following :



You may find red/green/yellow/black on the phone socket. In this case, wire as above. Note that the line may be on the orange pair, in that case observe the solid vs striped and wire as per the blue pair.
It all just depends on which pair eircom used, sometimes if there's a problem with the orange pair they wire on the blue etc.

Ignore any online info about UK wiring as it's not relevant to Irish telephone wiring structures which are generally more like north america.

If you get your hands on an eircom socket they call T1 and R1

L1
and
L2

Ignore the terminal marked R1 (it's only used if you're working with a very old installation and need to support old bell-ringer hardwired phones). Only connect 2 wires between extensions, not 3 as in the UK!

Daisy chaining one socket to the next is the preferred layout, but if it's not practical you an also use a star network where they all go back to a single junction box.
Also, if you add too many phones the line may not have enough power to ring them. This depends on a whole variety of factors, including distance from the local exchange, but as a rule of thumb don't go above 4 devices on one line.

flywheel

thanks for all the info, much appreciated