Electrical Requirements; Site Telephony Wiring Requirements; Digital Loop - Nortel BCM50 Installation And Maintenance Manual

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Electrical requirements

Electrical requirements
Ensure you meet the following electrical requirements:
• Power must be supplied from a non-switched, unobstructed outlet within 1.5 m (5 ft.) of the
BCM50 units.
• The supplied power must be a dedicated 110 V to 120 V ac nominal (or 220 V to 240 V ac
nominal), 50/60 Hz, 15 A minimum service with a third wire safety ground. The third wire
safety ground provides shock protection and prevents electromagnetic interference.
Danger: Risk of electric shock
The safety of this product requires connection to an outlet with a third wire ground. Use
only with the supplied BCM50 power supply and a three wire power outlet.
Caution: Check ground connections
Ensure that the electrical ground connections of the power utility, telephone lines, and
internal metal water pipe system, if present, are connected together. If these ground
connections are not connected together, contact the appropriate electrical inspection
authority. Do not try to make the connections yourself.
You can connect the BCM50 power supply to a power bar. The total length of the power cables
from the power supply to the electrical outlet (including power bar) must not exceed 2 m (6.5 ft.).
You must use a power bar approved by an appropriate National Test Body, with a third wire
ground. Do not use an extension cord between the power supply and the power bar, or between the
power bar and the electrical outlet.

Site telephony wiring requirements

This section describes the requirements for wiring digital telephony devices (digital loop) and
analog telephony devices (analog loop) to the BCM50 system.
Refer to the following sections for information on the parameters for digital and analog loops:
• "Digital loop" on page 84
• "Analog loop" on page 85

Digital loop

The following parameters must be met for a digital loop:
• one, two, or three twisted-pair cable(s) per telephone
dc loop resistance of less than 64 Ω
•
• cable length (0.5 mm or 24 AWG) less than 300 m (975 ft.)
Check the installation prerequisites