Outback Power Systems GFX International Series Operators Manual - Manual (Page 22)

Operation
20 900-0112-01-00 Rev B
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 the Absorption stage, or
when there is not enough energy to sustain selling.
The term “Silent” is also used in the context of stacking inverters and Power Save levels. See page 27.
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.
Target point: refloat setpoint or Re-Float Voltage setting, which activates the charger again. The
default setting is 12.5 Vdc (in a 12-volt system).
NOTE: If the MATE’s ac transfer control menu is set to gen, the charger skips both Sell and Silent, and
proceeds directly to Float stage. The same is true if the MATE3’s charger control menu is set to on. (It
will remain in Float until a new charge cycle is required, possibly through loss of AC power.) If ac
transfer control is set to grid (or if charger control is set to off), the charger goes through Silent as
noted and proceeds to Float only when the batteries drop to the Refloat voltage level. (See pages 14
and 15 for more information on this function.)
Float Stage
This is the third stage of charging. It is a constant-voltage stage. Current varies as needed to maintain
the voltage, but typically drops to a low number. This stage offsets the batteries’ tendency to
self-discharge (as well as the draw of any other DC loads), and maintains them at 100% of capacity.
Target point: float setpoint or Float Voltage setting. The default setting is 13.6 Vdc (in a 12-volt
system).
Time limit: float time period or Float Time setting.
If the voltage exceeds the Float voltage setting (usually due to another charging source), the inverter
can sell current to the loads (or the source) in an effort to bring the voltage down to the set point.
This will reduce the inverter’s draw from the AC source.
Float Timer
This is part of Float stage and is not a separate stage of charging. On the chart, it is marked as a
separate step to note that the timer only begins running upon reaching the Float set point. It does
not begin running at the beginning of Float stage. (The Float timer is reset to its maximum amount
whenever the batteries drop to the Refloat voltage.)
Repeated Silent
The unit re-enters the Silent mode as it did on page 20. The unit remains on the AC source, but the
charger is inactive.
Target point: refloat setpoint or Re-Float Voltage setting, which activates the charger again. The
default setting is 12.5 Vdc (in a 12-volt system).
The unit will continue cycling between Float and Silent for as long as the AC source is present.
However, if excess DC power is available and the batteries rise above the Sell RE set point, the unit can
re-enter Sell and begin selling the excess as described above.
The unit can only re-enter Sell when none of the timers are active. If any of the timers have accumulated
time while in Silent, the unit will enter the highest stage with accumulated time and proceed from
that point.