Installation manual

PS10270JENAA01 20/10/2004 69

Wiring the ISDN interface

ISDN cards have a T, S or S/T interface at BRI (S0/T0) or PRI capacity (S2/T2).

The S/T interface can be configured to supply:

• one connection at reference point S to a terminal

• one connection at reference point T to the network

These cards also handle the packet-mode data transmission service on channel D between the

network and a terminal.

You need 2 pairs to wire an ISDN interface: 1 transmit pair and 1 receive pair.

Wiring the T2/S2 interface

Depending on its switch settings, the LT2 card can be used to set up a connection to the T2 or

S2 reference point, thereby providing a speed of 2 Mbit/s (30B+D). Before beginning the wiring

procedure, check the setting of switch CA8 on the card.

Note: Use of T2 or S2 is confirmed during programming².

Each end of the L904-120 Ohm connection lead must be fitted with an ISO 8877 compliant male

RJ45 connector. One end must be connected to the PBX ground or the telephone shielding.

CAUTION

Make sure the polarity of the Tx/Rx pairs is correct.

The transmit and receive pairs are polarised. Make sure you do not reverse the polarities.

Two pairs are used to convey digital signals, one for each transmission direction. The pairs must not

be mixed up.

Transmit pair

at network termination

Recepive pair

at network termination

Shield

LT2 card