Lucent Technologies H569-420, Руководство по эксплуатации продукта

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Lucent Technologies ECS Minicell Battery Plant H569-420
3 - 2 Engineering and Ordering Issue 5 February 1997
other cases, additional rectifiers other than the redundant
rectifier may be required to provide the battery recharge current.
Plant Sizing
Example
The following example illustrates the relationship between mirc,
abh current drains, the recharge factor, and battery recharge
current.
A battery plant has the following parameters:
• a load current of 276 amperes
• an 8-hour discharge time (reserve time)
• recharge to 95% of battery capacity within 24 hours
From Figure 3-1, the recharge factor is 1.38.
mirc = abh x recharge factor
mirc = 276 x 1.38 = 380.9
Four 100 ampere rectifiers (380.9/100 = 3.8) are required to
provide the minimum installed capacity of 380.9 amperes for a
non-redundant system. However, if one rectifier fails, the
remaining rectifiers are not sufficient to support the abh
requirement. Therefore, one additional rectifier must be added to
ensure a redundant system.
Other
Considerations
Rectifiers having different output capacities should not be mixed
in the same battery plant.
Figure 3-1 illustrates several guidelines for choosing the
recharge factor.
• A minimum recharge factor of approximately 1.2 is
required to recharge the battery effectively.
• As the reserve time increases, the recharge factor required
to maintain a given recharge time must also increase.
• Continuing to increase the recharge factor above
approximately 1.4 does not significantly reduce the
recharge time.