Lucent Technologies -48V CPS4000/CPS4000 PLUS Cabinet Power System
Issue 13 December 2000
Engineering and Ordering 3 - 3
Engineering Information, continued
Plant
Configuration
Examples
To illustrate the relationships between mirc, abh current drains, the
recharge factor, and battery recharge current for non-redundant and
redundant systems, consider the following examples.
1. A battery plant is required to provide a load current of 34 amperes,
have an 8-hour discharge time (reserve time) and recharge to 95%
of battery capacity in 24 hours. Determine the number of 12.5A or
15A rectifiers required for non-redundant systems.
From Figure 3-1, the recharge factor is 1.38.
mirc = abh x recharge factor
mirc = 34 x 1.38 = 46.9 amperes
Four 12.5A rectifiers (46.9/12.5 = 3.8) or four 15A rectifiers (46.9/
15 = 3.1) are required to provide the minimum installed capacity of
46.9 amperes for a non-redundant system. If one 12.5 rectifier fails,
the remaining rectifiers will not provide the abh capacity, and one
additional 12.5A rectifier must be added to complete a redundant
system. If one 15A rectifier fails, the remaining rectifiers will
provide the abh capacity.
2. A two-shelf battery plant is required to provide a load current of
85A, have a 5-hour discharge time (reserve time) and recharge to
95% of battery capacity in 24 hours. Determine the number of
12.5A rectifiers required for non-redundant and redundant systems.
From Figure 3-1, the recharge factor is approximately 1.25.
mirc = abh x recharge factor
mirc = 85 x 1.25 = 106.3
Nine 12.5A rectifiers (106/12.5 = 8.5) are required to provide the
minimum installed rectifier capacity of 106.3A. In this example,
seven rectifiers supply the abh capacity and two additional
rectifiers are required to supply the battery recharge current. This
system also meets the requirements for non-redundant and
redundant systems.
