How many phone extension sockets can you have from a master?

[gjh]

Is there a limit to the number of extension sockets that you can run from the master socket [Telewest]? If you wish to have more extenions than the limit allows how can you get around the limit [if it is possible?].

I currently have a master socket downstairs and three extension sockets upstairs, one in each bedroom. I'd like a further two extension sockets downstairs. Do the two new sockets have to be put in series with the current extensions or is there any other way of wiring them?

 

[ChrisR]

As far as the phones are concerned they'll all be in Parallel. The traditional number is 3. 3 being the REN (Ringer Equivalence Number) limit per BT connection. You'd better ask Telewest what theirs is, and look on the bottom of your phones for each one's REN. Some may be 1.5 or 2, usually answerphones.

In practice you could exceed 3 on a BT line though eventually some ringers would stop working. A solution is/was to disconnect bells in some phones.

 

[spence_spark]

its also possible to purchase a REN expander
small box that connects in the circuit and i believe allows you to expand the REN as high as 16
i.e if the ren of your phone is 1 you can have upto 16!!

 

[breezer]

number of sockets doesnt matter, what does matter is has been said the REN, so you could have say 20 sockets, but you could only have up to 4 REN, so inother words with 20 sockets you could only have 4 phones plugged in.

You should connect them in paralell so that
terminal 2 goes to 2
terminal 3 goes to 3
terminal 5 goes to 5

 

[felix]

Warning: When you connect those phone sockets up, DO NOT believe the numbers on the terminals! I've found a number of phone sockets whose terminals were numbered in reverse. This doesn't stop the phone from working because the the voice signals use 2 and 5. Their polarity will be reversed but this hasn't upset any phones or modems (moda?) that I've got.

The problem is with the ringer on terminal 3 - because you've unknowingly put it on 4! Surprisingly, some phones will still ring, even with no ringer connection at all (two wires only) but others won't. I spent two hours trying to figure out why a particular phone wouldn't ring in one socket. I double checked continuity in all the sockets, falsely blamed a decorator for hacking at a phone wire while scraping wallpaper and even rang up BT's faults department to find out if there was a length limit on internal phone wiring - then I checked all the connections again.

I can't remember what prompted me to look carefully at those numbers but everything suddenly made sense. I strongly recommend that you work from pin positions in the outlet. Follow each one to its terminal and ignore anything printed on the board.

Here's another tip. If you're handy with wire strippers and a soldering iron, strip some insulation part way off one set of wires and solder the other set to the bared parts before pushing only the first ones into the terminals. This way if one of those IDC's goes bad you'll only have trouble at a single socket.