I am adding a standard telephone extension socket in an upstairs bedroom. To go from the master NTE5 (downstairs) to the bedroom I am routing the extension cable externally up the outside wall. For this purpose I thought it correct to buy external grade cable CW1128 (5 pair).

The wiring colour code does not allow me to identify the twisted pairs - ie 5 of the wires are white. How do I know which white wire is the pair to each colour?

Should I just be using CW1308 for this even though it goes outside.

What am i missing here? I am being stupid?!

HELP!

If they are all white, then you will have to bell out the cables to test which is which, and label each one.

Then it's just a case of linking pins 2,3 and 5 from the master to the slave socket.

EDIT: according to the following:


So you should be able to find a pair, which will get you the 2 and 5 sorted. You could then bell out a pair for pin 3, or find a phone that requires the ring capacitor and try ring the phone with one of the wires from the pair connected and then the other. (First check that the phone requires the ring capacitor).

If you strip the cable back far enough to see the twisting, you should see that each white wire is twisted with a coloured one. That is enough to identify which white one is which.
Good luck.