Digi 90031300 manual Planning the T1 WAN Interface, Carrier Approval, CSU Mode

Planning the T1 WAN Interface

This section describes planning the T1 Modem Bank interface to the carrier facility. The configuration of the T1 Modem Bank must match the requirements of the T1 line specified by the carrier.

Connections to the WAN

Connection to the telephone carrier facility is handled from the line card, via a T1 line.

Carrier Approval

Contact your carrier for approval before beginning the actual installation. By doing this, you will help to ensure proper configuration of the line and the T1 Modem Bank. This protects the T1 Modem Bank and telephone network from damage due to an improper configuration.

After the T1 Modem Bank has been installed on the network, it is good practice to contact the carrier before removing or disconnecting the T1 Modem Bank. If you disconnect the T1 Modem Bank from the WAN, the carrier may suspend your T1 service. RJ-45 connectors are available which ensure loopback upon disconnection of user equipment to ensure that the line from the central office is properly terminated. Most T1 carriers provide a “smart jack” which will loop the T1 carrier when the T1 Modem Bank is disabled.

CSU Mode

∙When the line card is in the CSU mode of operation (also known as “Long Haul”), it supports 6,000 feet of 24 AWG twisted-pair cable.

∙In the non-CSU mode of operation (also known as “Short Haul”), the DSX-1 function supports a maximum cable distance of 655 feet. This mode allows the T1 Line card to interface to PBX devices.

Planning the T1 Interface 3