Outback Power Systems GFX International Series Operators Manual - Manual (Page 23)

Operation
900-0112-01-00 Rev B 21
Figure 6 Repeated Charging Cycles
New Charging Cycle
If the AC source is lost or disconnected, the unit will return to inverting mode if enabled. The battery
voltage will begin to decrease due to loads or natural loss. When the AC source is restored, the
inverter will return to the charging cycle. If the batteries drop below the Rebulk voltage (see below),
the inverter will restart the cycle, beginning at Bulk stage. (See the triangle symbol
in Figure 6.)
If the batteries do not drop below Rebulk, the charger will not enter the Bulk stage and will return to
its previous stage.
New Absorption Stage
When entering the second stage, Absorption, the charger will not necessarily run through its full
duration. The timer will count down whatever time remains from the previous cycle, or whatever time
it has accumulated since then.
Absorption Timer
The Absorption timer does not reset to its maximum like the Float timer does. Instead, the timer
counts upward (gaining time) whenever the battery voltage drops below the Rebulk point. This
means that the Absorption period may not always be the same, depending on how much time it
has acquired.
In a 12-volt system, the Rebulk voltage is 12.2 Vdc. (All voltages in this section are given for a 12-volt
system.) This is a fixed setting and cannot be changed. For as long as the inverter remains below this
voltage, the Absorption timer will gain an equal amount of time. This dictates the duration of the
Absorption stage. Note that in
Figure 6 the duration of time spent below the Rebulk voltage is the
same as the subsequent Absorption period (as shown by the small arrows).
If the battery voltage drops below 12.0 Vdc (in a 12-volt system), the timer increments (counts
upward) at double the normal rate. For example, if the batteries spent 8 minutes below this voltage,
16 minutes would be added to the Absorption timer. Similarly, if the battery voltage drops below
11.8 Vdc (in a 12-volt system), the timer increments at quadruple the normal rate.
The Absorption timer continues this behavior even if the charger is still on. For example, if the charger
is in Float stage and there is a significant battery drain, the charger may not be able to maintain the
batteries at the Float voltage. Once the batteries fall below the Rebulk point, the Absorption timer will
begin accumulating time. (However, the accumulation will be minor, as this will also cause the
charger to re-enter the Bulk stage.)
The timer will stop incrementing when it reaches the absorb time limit or Absorb Time setting. This is
the maximum duration of the Absorption stage. This means that regardless of the voltage, the timer
No
Charge
Bulk
Absorption
Sell RE
AC Loss
Sell RE
Bulk
Absorption
Silent
Float
Absorption Set Point
Sell RE Set Point
Float Set Point
Refloat Set Point
Voltage
Time
Rebulk Point
Float
Timer