Xantrex Technology 806-1054 User Manual

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Freedom HF Owner’s Guide
Battery Charging
Battery charging is possible only when shore power is present and 
the Freedom HF unit is connected to a battery (or battery bank).
The frequency of battery charging is determined by how much 
energy in the battery is used up during inverting. Whenever the 
Freedom HF detects a battery voltage that falls below 12.8 volts, the 
unit will begin charging the battery, i.e., enter into bulk and 
absorption stages then settle in float stage. If battery voltage does 
not reach 5 volts after one minute or 10 volts after 15 minutes as 
shown in the graph, the unit will terminate the charging process and 
the error code  will show on the display screen.
Figure 4 illustrates the three-stage charging process used to 
maximize Freedom HF’s charging efficiency.
Figure 4 Three-stage Charging Process
15 min
Absorption V
Float V
10V
Absorption 
Bulk 
Float 
8 hrs 
5 hrs 
Voltage
Time
Charge 
Current 
Setting
Absorption 
to Float 
transition
Absorption 
Bulk 
Float 
Current
Time
NOTE: 
If an external DC load is 
connected to the 
battery and it drains the 
battery down to 12.8 
Vdc, the charger will 
start a new bulk stage.
NOTE: 
During the Float stage, 
the charger will provide 
up to the maximum set 
charge current to 
compensate for an 
external DC load on 
demand.
Maximum 
Charge 
Current 
Setting
5V
1 min
Freedom HF InvChg Owners Guide.book  Page 26  Tuesday, April 29, 2014  12:10 PM