User Instructions UM1M820BNA
Spec No. 1M820BNA (Model M820B) Issue AH, March 4, 2013
Spec No. 1M820DNA (Model M820D)
Chapter 1. Introduction 15
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For practical purposes, the battery capacity at the end of every recharge period is set to 100% as long as
Step1, Step 2, and Step 3 have elapsed.
If end of charge is not reached within the set maximum hrs, the recharge will be terminated anyway and
discharge cycle will be initiated.
The current available from the rectifiers can be programmed (in AMPS) from 10% to 121% of combined
rectifier capacity. The factory setting is 121% unless otherwise specified. The current available from the
converters can be programmed (in AMPS) from 50% to 116% of combined converter capacity. The factory
setting is 116% unless otherwise specified. Refer to the ACU+ Configuration Drawing (C-drawing)
supplied with your system documentation for your system’s settings.
If a rectifier or converter is added, the respective current limit point will automatically increase by the
percentage each existing rectifier or converter was set to provide prior to the addition.
If a rectifier or converter is removed from the system (and the Rect Comm Fail or Conv Comm Fail alarm
is reset), the respective current limit point will remain unchanged unless the capacity of the remaining
rectifiers or converters is not sufficient to maintain the present current limit point. If that happens, the
current limit point will automatically increase to the maximum (121% of the remaining rectifiers or 116% of
the remaining converters).