Use this free calculator to plan battery runtime with depth-of-discharge and inverter losses. Change the load, starting surge, losses and battery limits to match your equipment.
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Motors and compressors can need extra power when they start.
Battery age, temperature and a high discharge rate can reduce delivered energy.
Use this as a planning range. Confirm continuous rating, peak rating and battery compatibility with the manufacturer and a qualified installer.
Nominal battery energy is reduced by depth of discharge and inverter efficiency before it is divided by the average load.
Use the battery chemistry's recommended discharge limit and check manufacturer runtime curves at a similar load.
Dividing nominal Wh by load assumes every stored watt-hour reaches the appliances, which no real system achieves.
Backup hours = V × Ah × batteries × DoD × inverter efficiency ÷ load
Use the battery chemistry's recommended discharge limit and check manufacturer runtime curves at a similar load.
Dividing nominal Wh by load assumes every stored watt-hour reaches the appliances, which no real system achieves.
Use this as a planning range. Confirm continuous rating, peak rating and battery compatibility with the manufacturer and a qualified installer.