Product Manual

Operation
30 900-0161-01-01 Rev B
Time limit:
Absorb Time
setting. The charger does not necessarily run through its full duration
if it retained time from a previous cycle. The timer counts down from the inception of Absorption
stage until it reaches zero. The time remaining can be viewed in the system display.
The Absorption timer does not reset to its maximum amount, or to zero, when AC power is
disconnected or reconnected. It only goes to zero if the timer runs out during Absorption stage,
or if an external
STOP BULK
command is sent. In other cases it retains any remaining time.
Absorb Time
is reset to its maximum amount whenever the battery voltage decreases to the
Re-Bulk Voltage
. The reset occurs immediately, regardless of the time spent below this point.
To skip this step:
Setting
Absorb Time
to a very short duration causes the charger to spend
minimal time in Absorption once the Bulk stage is complete. Setting
Absorb Time
to zero will
cause the charger to skip both the Bulk and Absorption stages and proceed directly to the
constant-current Float stage. This may not be desired if the intent is to skip Absorption but
retain the Bulk stage.
Silent
This is not a charging stage, but a quiescent period between stages. The inverter remains on
the AC source, but the charger is inactive. It enters this condition upon completing a timed
stage such as Absorption, Float, or Equalize.
In Silent, the batteries are not in significant use by the inverter, but they are also not being
charged. The battery voltage will naturally decrease when not maintained by another means
such as a renewable source.
The term “Silent” is also used in an unrelated context regarding
Power Save
. See the
Power
Save
section of the
Installation Manual
.
Voltage Used:
Re-Float Voltage
setting. When the battery voltage decreases to this point, the
charger becomes active again. The default set point is 50.0 Vdc.
To skip this step:
Setting
Float Time
to
24/7
makes the charger remain in Float continuously
so that it does not proceed through the Silent, Bulk, Absorption, or Float timer steps.
Float Stage
This is the third stage of charging. It is sometimes known as maintenance charging. Float
stage balances the batteries’ tendency to self-discharge (as well as balancing the draw of any
other DC loads). It maintains the batteries at 100% of capacity.
Voltage Used:
Float Voltage
setting. The default set point is 54.4 Vdc. This setting is also
used by
Offset
when in this stage. (See page 36.) For the charger to work normally, this setting
needs to be higher than the
Re-Float Voltage
setting.
The charger may perform two functions during Float. Both are called
Float
in the system
display. They are defined here as
Refloat
and
Float
.
Refloat
Refloat is a constant-current function. The initial DC current may be as high as the charger’s
maximum current, depending on conditions. This stage is similar to Bulk, except that the
charger uses the
Float Voltage
setting as noted above. The charger delivers current until the
batteries reach this value.
Float
Float is a constant-voltage function. The charging current varies as needed to maintain
Float
Voltage
, but typically drops to a low number. This stage is similar to Absorption, except that the
voltage is different.