Lucent Technologies Lineage 2000 J85503B-2, Руководство по эксплуатации продукта

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Lucent Technologies Lineage
®
2000 200A Ferroresonant Rectifier J85503B-2
Issue 8 January 1999 Engineering and Ordering 3 - 3
defining a non-redundant system. A redundant system
additionally requires that the loss of any one rectifier does not
cause the remaining rectifier capacity to fall below the abh value.
This is another way of saying that the loss of any one rectifier in
the system does not cause the batteries to discharge. In some
cases, meeting the mirc current requirement also meets the
additional requirement for a redundant system; in other cases it
does not.
Sizing Example The following examples illustrate the sizing principles given
above.
1. The average busy hour current (abh) of a plant is 2850A.
The plant is required to have a 4-hour reserve (discharge)
time and a 24-hour recharge time. Calculate the minimum
installed rectifier capacity (mirc) and the number of 200A
rectifiers required in redundant and non-redundant
systems.
From Figure 3-1, a 24-hour recharge time intersects the
4-hour reserve curve at a recharge factor of approximately
1.2.
mirc = abh x recharge factor
mirc = 2850A x 1.2 = 3420A
The number of 200A rectifiers required to supply at least
3420A is nine (9 x 200A = 3600A). Nine rectifiers are
required in a non-redundant system. If one of the rectifiers
fails, the remaining rectifier capacity is 3200A (8 x 200A),
which is greater than the 2850A abh. Therefore, nine 200A
rectifiers are also sufficient for a redundant system.
2. The average busy hour current drain (abh) of a plant is
210A. The plant is required to have an 8-hour reserve time
and a 24-hour recharge time. Calculate the mirc and the
number of 100A rectifiers required in redundant and
non-redundant systems.
From Figure 3-1, a 24-hour recharge time intersects the
8-hour reserve curve at a recharge factor of approximately
1.38.