Connecting E1/T1 Trunks For Pstn Fallback; Connecting To Isdn Bri Lines; Figure 2-8: Pstn Lifeline For Pri E1/T1 - AudioCodes Mediant 600 Installation Manual

2.4.4

Connecting E1/T1 Trunks for PSTN Fallback

The device offers a PSTN Fallback feature when provided with two E1/T1 PRI spans. The
digital module's Port II serves as a dedicated Fallback port connected to the PSTN. In the
event of a power failure (i.e., no Ethernet link), a relay connects ports I and II by the closing
of a metallic switch inside the module, re-routing trunk traffic from the PBX to the PSTN is
established (instead of from the PBX to the IP network).
Notes:
2.4.5

Connecting to ISDN BRI Lines

The device can house up to two BRI modules, each supporting four BRI ports, thereby
providing a total of up to 8 BRI ports.
Note:
Warning:
Installation Manual

Figure 2-8: PSTN Lifeline for PRI E1/T1

•
Only ISDN supports the PSTN Fallback feature when the number of
supported channels (e.g., 30) is less than the maximum number of
possible channels provided by the physical ports (e.g., two E1 trunks).
When the number of supported channels (e.g., 60) equals the maximum
number of channels provided by the physical ports (e.g., two E1 trunks),
then other protocols such as CAS are also supported.
•
This PSTN Fallback feature has no relation to the PSTN Fallback
Software Upgrade Key.
BRI interface is applicable only to devices running the SIP protocol.
To protect against electrical shock and fire, use a 26 AWG min wire to
connect the BRI ports to the PSTN.
20
Mediant 600
Document #: LTRT-85605