Analogue phone wiring in UK 1

[DenisOxon2]

Hopefully a simple question......

Analogue phone require pins 2 and 5 on the wall socket to provide a service.

If you are connecting them to a pabx and wish to transfer call, will this still operate with only two wires ? If not which ones do I connect back to pabx ? The wiring diagram for card in pabx shows 4 wires connected, but no where can I find how many wires are needed at phone.

 

[Westi]

all analog phone have 2 wires only. Not sure where your 4 wires come from and what their function would be. 2 is enough for analog as long as you don't need to use ground for anything but that is more 80's technology as we use flash these days to do the same.
again 2 wires is all you need, sorry about the mumbling had 2 glasses of wine already

Joe W.

FHandw, ACSS (SME)


"This is the end of the world, make sure to buy your T-shirt before it is too late"
Original expression of my daughter

 

[DenisOxon2]

Thank you Joe. I realise that for normal operation 2 wires is enough. But if you have phone on a pabx and it wants to transfer calls, using Recall button (press R followed by new extension), does that option need extra wires ?

 

[Dexman]

Wouldn't those functions be handled internally by the PBX itself? Single pair is really all that is needed for an SLT.

In the past, US basic telephone jacks have been connected with 4 wires. The conductor jackets are colored green, red, black and yellow. Today, 4-pair cable tends to be the go-to medium.

I "FEATURE 00"

http://dexman.webs.com/

 

[sbcsu]

Hi,
2 wires are normal wired out from PBX to End User Extension.
2 wires are normal wired from PTT Provider to PBX

If pin 3 is connected that is the 'bell wire'.
There are no ringing capacitors in UK telephones, the Capacitor is in the 'master' socket.

If you want to run parallel phones from the master socket you need to run a wire from pin 3 out to a slave socket
So 2 & 5 for the line and 3 for the bell from the master socket out to the slave socket.

Pin 4 was used as Earth Recall - not used anymore -
Timed Break Recall is normally used now 100 milliseconds of a break sends a signal to put call on hold and return new dial tone.
On the back of the phone you set it to DTMF & TBR for tone dialling and timed break recall