Most multi-phase charge controllers offer pre-programmed Equalization schedules commonly referred to as preventative equalizations. These are typically set to run for a shorter 1-2 hour period every 30, 60 or 90 days and may be beneficial in balancing and removing small amounts of accumulated sulfation on an ongoing basis.
It should be noted that running frequent equalizations on batteries which do not require balancing or desulfation will overcharge and deteriorate the cells prematurely, shortening the life of the battery. For this reason, Rolls recommends monitoring specific gravity and voltage on a regular basis to ensure scheduled Equalization times are appropriately set. Alternatively, a corrective Equalization may be necessary if symptoms arise such as running a backup generator more frequently (low capacity) or the battery bank will “no longer hold a charge”. These symptoms are typical of heavy, accumulated sulfation.
If a battery is not being fully charged on a regular basis or limited or inadequate Equalization is performed using a generator, sulfating will occur from “deficit” cycling‘. This undercharge and buildup will gradually lower available capacity. It is best to monitor the condition of the bank regularly as accumulation of sulfation may take months to reach a point where the loss is noticeable.
NOTE: Properly charging a battery bank with sufficient voltage and current on each cycle is essential to long cycle life. Equalizations may be required periodically to balance and desulfate but should not be relied on to compensate for insufficient charging sources. This procedure may not fully recover a loss of capacity from a buildup of sulfation over time. Repeated Equalizations may be required in situations where the battery bank has been consistently undercharged. Recovered capacity, generally partial, may take 1-3 months with monitoring and repeated procedures
in battery banks with consistently low specific gravity measurements.