Nortel Circuit Card, Installation Manual, Page: 653 / 908

NT8D15 E&M Trunk card Page 653 of 906
Circuit Card Description and Installation
Effective loss See pad table (Table 209 on
page 662 )
See pad table (Table 209 on
page 662 )
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