Outback Power Systems GFX Series Inverter/Charger Operators Manual - Manual (Page 24)

Operation
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900-0114-01-00 Rev A
Equalization follows the same pattern as standard three-stage charging, as shown in Figure 4.
However, instead of the Absorption voltage and time set points, it is controlled by the equalize set
point and equalize time period settings in the system display.
Equalization is normally performed only on flooded lead-acid batteries. The schedule for equalization
varies with battery use and type, but it is usually performed every few months. If performed correctly,
this process can extend battery life by a considerable amount.
Equalization is not normally performed on nickel-technology batteries or any sort of sealed battery.
CAUTION: Battery Damage
 Never perform equalization on sealed gel-cell batteries. This process will
destroy them.
 Contact the battery manufacturer for recommendations on equalization
voltage, duration, schedule, and/or advisability. Always follow
manufacturer recommendations for equalization. Do not equalize any
battery unless approved by the manufacturer.
Battery Temperature Compensation
Temperature compensation is a process that corrects for changes in battery performance caused by
varying temperature.
When batteries are cooler than room temperature (25 °C or 77 °F), the electrolyte reaction slows down.
This causes the battery to accept charging energy less readily. Delivering the usual amount of energy
that would fully recharge a battery at room temperature will undercharge a cool one.
Conversely, when batteries are warmer than room temperature, the electrolyte reaction is somewhat
hyper-reactive. It takes less energy than usual to charge them. Delivering the full (room-temperature)
amount of energy would overcharge them and can be hard on them over time.
The inverter, when equipped with the Remote Temperature Sensor (RTS) will compensate for changes
in temperature. The RTS is attached to a single battery near the center of the bank, to achieve a
representative temperature. If installed in a multiple-inverter system, only a single RTS is necessary. It
must be plugged into the master inverter, and will control the charging of all slaves and all charge
controllers. (See the GFX Series Installation Manual to locate the RTS port.) This process is automatic.
When charging, an inverter system with an RTS will increase or decrease the charge voltage by 5 mV
per degree Celsius per battery cell. This setting affects the Absorption, Float, and Equalization set
points. The Sell RE and Refloat set points are not temperature compensated. The Equalization set
points are not compensated in OutBack charge controllers.
 In a 12 Vdc system (6 cells, 2 volts each), this means 0.03 volts per degree Celsius above or below 25 °C.
Maximum compensation is ± 0.6 Vdc.
 In a 24 Vdc system (12 cells, 2 volts each), this means 0.06 volts per degree Celsius above or below 25 °C.
Maximum compensation is ± 1.2 Vdc.
 In a 48 Vdc system (24 cells, 2 volts each), this means 0.12 volts per degree Celsius above or below 25 °C.
Maximum compensation is ± 2.4 Vdc.
Examples:
 A 12 Vdc system with batteries at 10 °C will compensate its charging to 0.3 Vdc higher than the set points.
 A 24 Vdc system with batteries at 35 °C will compensate its charging to 0.6 Vdc lower than the set points.
 A 48 Vdc system with batteries at 15 °C will compensate its charging to 1.2 Vdc higher than the set points.