You should enable the CONF ROOM in PGM231, if you use ISDN/PRI/BRI and DDI.
Also read this very good description, below:
Internal and external calls can participate in a conference.
You select which of the 9 conference room you want to use.
There can be up to 3 conference members in each conference room at the LDK-24.
There can be up to 15 conference members in each conference room at LDK-50/100.
Password for each conference room may be required.
These are the "automatic" conferences, ie. there is no local conference leader.
Operating from LG system device:
To enable the use of a conference room on the phone
(1). Press [TRAN/PROG] + 4 + 3 + Room number (1 ~ 9)
(2). Enter 5-digit password. (Could possibly be omitted).
(3). Press [HOLD/Save] button.
In order to de-activate the use of a conference room on the phone:
(1) Press [TRAN/PROG] + 4 + 4 + Oonf room number (1 ~ 9)
(2). Enter 5-digit password, the password is used to activate the conference room.
(3) Press [HOLD/Save] button.
To participate in a conference in one of the 9 conference rooms:
(1) Call the conference by typing 57 + room no.1-9. (= 571 ~ 579)
(2) Enter your password (if the password is used to activate the conference room) and join.
Simple and easy & it works as it should.
In PGM 231 you may enter a conf room in the PBX's night or weekend position, just to let your employees have a conference after the football match on Saturday - for "after the game " discussions!
///doktor