Outback Power Systems GFX1424E, GFX1312E, GFX1448E Equalization, Battery Temperature Compensation

Operation

will always run for the full Absorption period if the batteries dropped below the appropriate voltage for that amount of time. If significant battery drain caused them to drop below the set points for doubling or quadrupling the rate, it may run for the full Absorption period even after a lesser amount of time.

The rest of the charging stages will proceed as described on the previous few pages.

Equalization

Equalization is a controlled overcharge that is part of regular battery maintenance. Equalization brings the batteries to a much higher voltage than usual and maintains this high voltage for a period of time. This has the result of removing inert compounds from the battery plates and reducing stratification in the electrolyte.

This process must be started manually using the system display. The inverter cannot be programmed for automatic battery equalization. This is a safety measure.

Equalization follows the same pattern as standard three-stage charging, as shown in Figure 5. However, instead of the Absorption voltage set points, it is controlled by the equalize set point or Equalize Voltage settings in the system display. The time is controlled by the equalize time period or Equalize Time setting.

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

¾Do not equalize any sealed battery types (VRLA, AGM, Gel, or other) unless approved by the manufacturer. Some batteries may suffer severe damage from equalization.

¾Contact the battery manufacturer for recommendations on equalization voltage, duration, schedule, and/or advisability. Always follow manufacturer recommendations for equalization.

Battery Temperature Compensation

Battery performance will change when the temperature varies above or below room temperature (77°F or 25°C). Temperature compensation is a process that adjusts battery charging to correct for these changes.

When a battery is cooler than room temperature, its internal resistance goes up and the voltage changes more quickly. This makes it easier for the charger to reach its voltage set points. However, while accomplishing this process, it will not deliver all the current that the battery requires. As a result, the battery will tend to be undercharged.

Conversely, when a battery is warmer than room temperature, its internal resistance goes down and the voltage changes more slowly. This makes it harder for the charger to reach its voltage set points. It will continue to deliver energy as time passes until the charging set points are reached. However, this tends to be far more than the battery requires, meaning it will tend to be overcharged.