Brochures and Data Sheets

NetSure
™
ACU+ Controller (Advanced Control Unit Plus)
User Instructions, UM1M820BNA (Issue AK, March 3, 2014)
Spec. No: 1M820BNA, 1M820DNA Code: UM1M820BNA
Model No: M820B, M820D Issue AK, March 3, 2014
10
If end of charge is not reached within the set maximum hrs, the
recharge will be terminated anyway and discharge cycle will be
initiated.
Maximum Current Limit Function
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).
When setting total rectifier or total converter current limit, the set
point to each unit is the total set point divided by the number of
units. For example, if the system contains five rectifiers and the
current limit is set to 150 amps then each rectifier has a current
limit set point of 30 amps. If one or more rectifiers or converters
are removed or fail it will take several seconds for the individual set
points to the remaining rectifiers or converters to be reset. In the
example given, if one rectifier is removed the current limit set
point will drop to 120 amps (30 amps times four remaining
rectifiers) until the controller can send updated set points to the
remaining rectifiers. This takes a couple communication cycles
(several seconds) after which each rectifier would have a new set
point of 37.5 amps for a total of 150 amps. The total current limit
of the rectifiers and converters should not be set such that the loss
of the redundant rectifiers or converters will cause this temporary
set point to drop below the actual maximum expected load. If
batteries are used on the rectifier output, the batteries should
support the load until the current limit set points can be re-
established due to loss of a rectifier.