Nortel Meridian 1 Option 11C Compact, Technical Reference Manual, Page: 106 / 148

Chapter 9 — NTMW05 Digital Line Card Page 95 of 136
Meridian 1 Option 11C Compact Technical Reference Guide
Technical summary
Table 32 provides a technical summary of the digital line card.
Table 32
NTMW05 Digital Line Card technical summary
Power requirements
The digital line card needs +15V DC over each loop at a maximum current of
80 mA. It re15V, - 15V, and +5V from the backplane. The line feed
interface can supply power to one loop of varying length up to 3500 ft
(1070 m) using 24 AWG wire with a maximum allowable AC signal loss of
15.5 dB at 256 kHz, and a maximum DC loop resistance of 210 ohms;
26 AWG wire is limited to 2450 ft (745 m).
Foreign and surge voltage protections
In-circuit protection against power line crosses or lightning is not provided on
the Digital line card.
Characteristics Description
Units per card 24 voice, 8 data
Impedance 100 ohms
Loop limits 0 to 3500 ft (1070 m) with 24 AWG cable
(+15 V DC at 80 mA)
0 to 2450 ft (745 m) with 26 AWG cable
Line rate 512 kbps + 100 ppm
Power supply + 5 V DC
+15 V DC
+10 V DC
Transmitter output voltage:
—successive “1” bits +1.5 + 0.15 V and -1.5 + 0.15 V
—”0” bits 0 + 50 mV