Cisco CPA2501, User Manual

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Preparing to Install the Router 2-7
Preparing to Connect to a Network
ISDN Connections
Use a BRI cable (not included) to connect the router directly to an ISDN. (See Table 2-1.)
Warning
Network hazardous voltages are present in the BRI cable. If you detach the BRI
cable, detach the end away from the router first to avoid possible electric shock. Network
hazardous voltages also are present on the system card in the area of the BRI port (RJ-45
connector), regardless of when power is turned OFF. (To see translated versions of this
warning, refer to the Regulatory Compliance and Safety Information document that
accompanied your router.)
Warning
The ISDN connection is regarded as a source of voltage that should be
inaccessible to user contact. Do not attempt to tamper with or open any public telephone
operator (PTO)-provided equipment or connection hardware. Any hardwired connection
(other than by a nonremovable, connect-one-time-only plug) must be made only by PTO
staff or suitably trained engineers. (To see translated versions of this warning, refer to the
Regulatory Compliance and Safety Information document that accompanied your router.)
Table 2-1 lists the specifications for ISDN BRI cables. Refer to the section “ISDN BRI Port
and Cable Pinouts” in the appendix “Cable Specifications” for pinouts.
1. nF = nanoFarad.
Table 2-1 ISDN BRI Cable Specifications
Specification High-Capacitance Cable Low-Capacitance Cable
Resistance (at 96 kHz) 160 ohms/km 160 ohms/km
Capacitance (at 1 kHz) 120 nF
1
/km 30 nF/km
Impedance (96 kHz) 75 ohms 150 ohms
Wire diameter 0.024 in. (0.6 mm) 0.024 in. (0.6 mm)
Distance limitation 32.8 ft (10 m) 32.8 ft (10 m)