Lucent Technologies 555-230-128 manual Install the BRI Terminating Resistor

DEFINITY Enterprise Communications Server Release 6	Issue 3
Installation and Test for Compact Modular Cabinets 555-230-128	May 1998
1 Install and Cable the Cabinets
Install the BRI Terminating Resistor	Page 1-77

Install the BRI Terminating Resistor

The resistors balance the cable plant between the receiver and the transmitter on the interface. When using the TN2198 ISDN-BRI 2-Wire U Interface circuit pack, an NT1 is required. A terminating resistor is always required near the terminal when the BRI S-type interface circuit pack (TN556 BRI 4-Wire S-NT Line circuit pack) is used (see #5ESS Switch Integrated Services Digital Network Customer Premises Planning Guide, 533-700-100).

The resistor is built into the NT1 and can be 1 of 3 values, depending on the configuration and the distance from the NT1 to the ISDN terminal. The resistor value is controlled from the NT1. A terminating resistor adapter may be needed near the terminal and can be placed in the satellite closet or work location.

! CAUTION:

The 440A4 terminating resistor and 110RA1-12 terminating resistor block are UL listed. Most new installations are the 110RA1-12 terminating resistor block. The following installation instructions should be observed.

■Never install telephone wiring during a lightning storm.

■Never install telephone jacks in wet locations unless the jack is specifically designed for wet locations.

■Never touch uninsulated wires or terminals unless the telephone line has been disconnected at the network interface.

■Use caution when installing or modifying telephone lines.