Wednesday, August 22, 2007

3Com V3000 ATA Ringing on UK Phones

I've been configuring a 3Com V3000 VOIP PABX. If you want to connect a UK spec phone you need to ensure you use a "PSTN full master". "PABX Masters" or "Secondary adapters" will not allow the phone to ring.

A UK PSTN Full Master contains a capacitor, resistor and spark suppressor. If you use anything other than a PSTN Master you can use the phone to make calls but it will not ring.

There are many different PSTN Masters available with different pinouts. I have sucessfully tested the following Krone part:-

Krone P/N : 6536/1/601/11

3Com 4500 default admin password

I have been configuring a 3Com 3CR17571-91 POW switch this week. Again the default password is not listed in the manuals. The admin username is : admin and the default password is blank. Hope that saves you some time if you are setting up one of these.

So far I'm not impressed with the quality of documentation from 3Com.

3Com V3000 BRI Admin password

I could not find this anywhere in the 3Com manuals. The default admin password for a 3Com V3000 is :-


(tha's 4 zeros)

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.