Nortel Networks Circuit Card User Manual

Page 618 of 906

NT8D14 Universal Trunk card

553-3001-211 Standard 3.00 August 2005

Jumper strap settings

For most applications, the jumper strap settings remain set to the standard
configuration as shipped from the factory. See Table 190 on

page 616

The jumper strap settings must be changed, as shown in Table 191 on

page 617

, for the following:

•

For CO/FX/WATS or TIE trunk loops exceeding 1524 meters (5000 ft.)

Table 192
Trunk types – termination impedance and balance network (NT8D14BA, NT8D14BB)

Trunk types

Terminating
impedance
(Note 1)

Balance network for loop lengths (Note 2)

0–915 m

(0–3000 ft)

915–1524 m

(3000–5000 ft)

> 1524 m

(> 5000 ft)

CO/FX/WATS

600 or 900
ohms

600 ohms

3COM

3CM2

2-way TIE (LDR)

600 or 900
ohms

600 ohms

3COM

3CM2

2-way TIE (OAID)

600 or 900
ohms

600 ohms

3COM

3CM2

DID (loop length
< 600 ohms)

600 or 900
ohms

600 ohms

3COM

3CM2

DID (loop length
Š 600 ohms)

600 or 900
ohms

600 ohms

N/A

3CM2

RAN: continuous
operation mode

600 or 900
ohms

600 or 900 ohms

N/A

Paging

600 ohms

N/A

Note 1: The terminating impedance of each trunk unit is software selectable in LD 14 and
should match the nominal impedance of the connecting equipment.

Note 2: The balance network of each trunk unit is software selectable between resistive 600 or
900 ohms or 3COM and jumper selectable between 3COM and 3CM2. Jumper selection for
3COM/3CM2 restriction does not apply to NT8D14BB.