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QPC578 Integrated Services Digital Line Card
Page 259 of 290
Line cards
Description
Power requirements
Table 72 shows the maximum power consumed by the QPC578 Integrated
Digital Services Line Card. The ISDLC pr30 V dc over each loop at
a maximum current of 60 mA. The line feed interface can supply power to
loops of up to 1067 m (3500 ft) in length using 22 or 24 AWG wire; 26 AWG
wire is limited to 747 m (2450 ft).
Foreign and surge voltage protections
The integrated services digital line card does not provide in-circuit protection
against power line crosses or lightning strikes. When the card is used to
service off-premise telephones, primary and secondary main distribution
frame (MDF) protection must be installed. Details on installing protection
devices are given in “Off-premise line protection” on page 48. Off-premise
telephones served by cable pairs routed through the central office, or crossing
a public right-of-way, can be subject to a requirement for on-card protection,
and MDF protectors may not be acceptable. Check local regulations before
providing such service.
Table 72
Integrated services digital line card—power consumption
Voltage
Current (max.)
–48 V dc or –52 V dc
180 mA
± 6 V dc
50 mA
±15 V dc
500 mA
+10 V dc
50 mA
Summary of Contents for NT1R20
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Page 76: ...Page 52 of 290 Description 553 3001 105 Standard 5 00 June 1999 ...
Page 154: ...Page 130 of 290 NT5D11 Line side T1 Interface Card 553 3001 105 Standard 5 00 June 1999 ...
Page 276: ...Page 252 of 290 QPC452 Basic 500 2500 Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Page 306: ...Page 282 of 290 List of terms 553 3001 105 Standard 5 00 June 1999 ...
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