User Manual

Off-grid Renewable Energy systems are typically sized to operate between 20%
and 50% DOD. Deep cycle batteries should be used to a maximum 50% DOD as
this offers a balance between capacity vs. cycle life, also taking into consideration
the cost of replacement.
For grid-connected backup systems, Installers will typically size battery banks to
operate to a greater depth of discharge to lower initial installation costs. Cycling of
grid-connected systems is significantly less frequent than off-grid applications
where this typically occurs on a daily basis. With infrequent cycling, a maximum
80% DOD is acceptable as long as the customer understands that the overall
cycle life is affected when the battery bank is discharged beyond 50% SOC.
These systems should not be designed to fully discharge the battery bank.
CYCLE LIFE VS. DEPTH OF DISCHARGE – ROLLS BATTERY ENGINEERING
SERIES 5000 WITH ADVANCED NAM
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