3Com V3000 ATA to UK Phones

I've been configuring a 3Com V3000BRI PABX this week and have had some difficulty connecting the ATA ports to UK phones. First it's inportant to understand that UK approved phones use different pins to USA phones. This means you cannot connect a UK phone to a 3Com ATA using a RJ11 straight through lead. The diagram above shows how UK approved phones and UK phone cords work.

If you want to connect a UK approved Telephone to an item of USA equipment you need to make a RJ11 lead like this:-

Here is the full end to end pinout

It's really annoying that the 3Com documentation does not show the pinouts of the ATA RJ11 sockets.