Nortel Networks Circuit Card User Manual
Page 653
NT8D15 E&M Trunk card
Page 653 of 906
Circuit Card
Description and Installation
Effective loss
See pad table (Table 209 on
)
See pad table (Table 209 on
Terminating impedance
600 ohms
600 ohms
Balance impedance
N/A
600 ohms
Table 203
Electrical characteristics of trunk cards
Characteristic
DID Trunk
CO trunk
Nominal impedance
600 or 900 ohms, (selected
by software)
600 or 900 ohms, (selected
by software)
Signaling range
2450 ohms
1700 ohms
Signaling type
Loop
Ground or loop start
Far-end battery
-42 to -52.5 V
-42 to -52.5 V
Near-end battery
N/A
-42.75 to -52.5 V
Minimum loop current
N/A
20 mA
Ground potential difference
+ 10 V
+ 3 V
Low DC loop resistance
during outpulsing
N/A
300 ohms
High DC loop resistance
N/A
Ground start equal to or
greater than 30 kS. Loop start
equal to or greater than 5 MS
Line leakage
Equal to or greater than 30
kS (Tip to Ring, Tip to GND,
Ring to GND).
Equal to or greater than 30
kS (Tip to Ring, Tip to GND,
Ring to GND)
Effective loss
See pad table
See pad table
Table 202
Electrical characteristics of E&M trunk cards (Part 2 of 2)
Characteristic
4-wire trunk
2-wire trunk