Dc power – Nortel Networks COMMUNICATION SERVER 1000 NN43021-110 User Manual
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System architecture
). An AC-powered system that does not require long-term
backup can benefit from a UPS with short-term backup because the UPS
typically provides power conditioning during normal operation, as well as
reserve power during short outages or blowouts.
Figure 17
ExternalAC-power architecture with reserve power
DC power
DC-powered systems always require external rectifiers to convert
commercial AC power into the standard –48 V DC required within the
system (see
Figure 18 "ExternalDC-power architecture with reserve power"
). Batteries are generally used with DC-powered systems, as
the traditional telecommunications powering method is for the rectifiers to
continuously charge a bank of batteries, while the system power "floats"
in parallel on the battery voltage. However, batteries are only required
if reserve power is needed.
A variety of rectifiers and distribution equipment can be used to supply
external DC power. Existing customer equipment can be used or a system
that Nortel either supplies or recommends, such as the Small or Large
Candeo, can be used. The Small Candeo is appropriate for Single Group
or Multi Group systems that do not require more than 300 A, while the
Large Candeo is suitable for larger systems. In all cases, equipment
for rectification and distribution is required, while reserve batteries are
optional.
Nortel Communication Server 1000
Communication Server 1000M and Meridian 1 Large System Overview
NN43021-110
02.05
Standard
30 September 2008
Copyright © 2003-2008 Nortel Networks
.