Outback Power Systems GFX1448E manual New Charging Cycle, New Absorption Stage, Absorption Timer

						Operation
Voltage				Absorption
Absorption Set Point		Absorption
Float Set Point
Sell RE Set Point					Silent		Float
						Float	Timer
Refloat Set Point		Sell RE		Sell RE
Rebulk Point
			AC Loss	Bulk
No	Bulk
Charge
		Time
		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

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