Power-Related Hardware; System Auxiliary Power - AT&T MERLIN LEGEND Release 3.1 System Manager's Manual

Power-Related Hardware

Power-Related Hardware
Your AT&T representative can plan for added power-related hardware to
provide your system with additional power and protection from power surges,
although most systems do not need extra surge protection. Other accessories
apply to system-specific conditions.
Power Accessories
In a power failure, battery backup units can keep the system running for several
hours. When you connect adjuncts and adapters to telephones, the power
requirements for the telephones and the system increase. Sometimes it is
necessary to add a power accessory, described in this section, to an individual
telephone or to the system to accommodate these additional needs.

System Auxiliary Power

When your system is installed, when you change the system operating mode, or
when you expand your system, an AT&T technician calculates the unit load on
your system and determines your overall power needs. A unit load is a measure
of power used to determine the electrical load that the following components
have on each carrier's power supply:
Telephones and adjuncts
800 DID modules
Only the telephones and adjuncts that connect to the analog and MLX extension
jacks on the control unit require unit load calculation, not equipment that has its
own power supply (for example, a fax machine, an MFM, or an answering
machine). If, after a system is changed, additional power is required for the
control unit, your AT&T representative will see that an auxiliary power unit is
installed.
NOTE:
Some system power supplies limit the number of 100D modules and 800 NI-BRI
modules (Release 4.0 and later systems only) installed in a carrier. A newer
power supply, the 391A3, eliminates the restriction. Consult your AT&T
representative for details.
System Components
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