Page370 of 544 NT8D02and NTDK16 Digital Line Cards
553-3011-100 Standard14.00 January 2002
Power requirements
The digital line card needs +15V DC over each loop at a maximum current of
80 mA. It requires +15V, -15V, and +5V from the backplane. The line feed
interface can supply power to one loop of varying length up to 1070 m
(3500ft) 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;
26AWG wire is limited to 745 m (2450 ft).
Foreign and surge voltage protections
In-circuit protection against power line crosses or lightning is not provided on
the Digital line card.