3.2. ISDN Basic Rate Interface (BRI) connection

The Abilis ISDN-BRI ports are electrically configured like Telecom NT1 ports, so:


The ports which are configured at a logical level as NT must always be connected to a 100 ohm impedance matching adapter.

Figure 3.2. Typical connecting scheme between Abilis - ISDN lines

Typical connecting scheme between Abilis - ISDN lines


Interesting chapters:

Section 2.9.2, “QPRIX”;

Section 2.9.4, “PB44X”;

Section 2.9.7, “BRI-HFC4 / BRI-HFC8”;

Section 75.1, “How to configure ISDN ports to connect PBX or ISDN lines”.

3.2.1. Emergency connection

If necessary (in case of damages, bad functioning, lack of electricity …) the user can manually by-pass Abilis and connect the switchboard to the Telecom network. Antek suggests the following procedure:

  • Disconnect the cable between the PBX switchboard and the impedance matching adapter.

  • Disconnect the cable between the Telecom line and the Abilis port, keeping the impedance matching adapter.

  • Connect the straight cable from the switchboard to the Telecom one using the impedance matching adapter.

  • Repeat this procedure for every line you want to by-pass.

Figure 3.3. Emergency procedure (by-pass Abilis)

Emergency procedure (by-pass Abilis)


To restore the telephone connections we suggest to write down precise instructions about the emergency procedure and keep them on hand in the switchboard room, available to technicians. Switch

To make the by-pass easier Antek provides Section 2.10.6, “RJ Switch” on request.