Outback Power Systems GS4048A Operators Manual - Manual (Page 29)

Operation
900-0161-01-00 Rev A 27
Battery Charging
IMPORTANT:
Battery charger settings need to be correct for a given battery type. Always
follow battery manufacturer recommendations. Making incorrect settings, or
leaving them at factory default settings, may cause the batteries to be
undercharged or overcharged.
Charge Current
Batteries or battery banks usually have a recommended limit on the maximum current used for
charging. Often this is calculated as a percentage or fraction of the battery capacity, represented by
“C”. For example, C/5 would be a DC amperage figure that is 1/5 of the total amp-hours of the bank.
Any chargers must be set so that the peak charge current does not exceed the recommended
maximum. If multiple chargers are present (including other chargers besides the Radian), this
calculation must accommodate the total combined current. The Radian’s charger may need to be set
at less than maximum. The system display can be used to change charger settings.
IMPORTANT:
Although the recommended current is generally represented in DC amperes, the Charger
AC Limit setting is measured in AC amperes, which are not measured on the same scale.
To convert the recommended DC current into a usable AC figure, divide the DC figure by
4 and round up. The result can be used as a charger setting for the Radian inverter.
Examples:
1) Battery bank consists of 8 x L16 FLA batteries in series. Recommended
maximum charge current is 75 Adc.
75 ÷ 4 = 18.75 or 19 Aac.
2) Battery bank consists of 12 x OutBack EnergyCell 200RE VRLA batteries in
series/parallel. Recommended maximum charge current is 90 Adc.
90 ÷ 4 = 22.5 or 23 Aac.
The maximum DC charge rate for Radian models is specified in Table 12 on page 61. The actual
Charger AC Limit setting is available in the AC Input and Current Limit menu of the MATE3 system
display. See Table 16 on page 65. These numbers are also summarized in Table 2 below. If multiple
Radian inverters are installed, divide the total current by the number of inverters and program each
with the resulting number.
Table 2 Charge Currents for Radian Models
Model Maximum DC Output (sent to battery) Maximum AC Input (used from source)
GS8048A 115 Adc 30 Aac
GS4048A 57.5 Adc 15 Aac
Charge Cycle
The inverter uses a “three-stage” battery charging process which is designed around batteries using
lead-acid chemistry. The three stages are Bulk, Absorption, and Float. These stages follow a series of
steps, which are shown on graphs and described in text (see page 28). On the graphs, the transitions