Inverter & Battery Size Calculator

Inverter & Battery size calculator

Total Backup Load (Watts):

Required Backup Time (Hours):

Battery System DC Voltage: 12V DC (Single Battery - Small Setup) 24V DC (2 Batteries - Medium Setup) 48V DC (4 Batteries - Large/Telecom Setup) 96V DC (8 Batteries) 120V DC (10 Batteries)

Battery Chemistry (DoD Limit): Tubular Lead-Acid (70% Max DoD) Flat Plate Lead-Acid (50% Max DoD) Lithium-Ion / LiFePO4 (85% Max DoD)

Inverter Overload Safety Margin: 20% Safety Cushion 25% Safety Cushion (Standard CPWD Practice) 40% Safety Cushion (High Inductive Loads)

System Sizing Results

Calculated Continuous VA Demand: 0.0 VA

Recommended Inverter Capacity

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Enter parameters to run calculation.

Required Battery Bank Capacity

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Calculated at specified discharge limit.

Note:

• Inverter Sizing (VA): Active Load (Watts) is divided by the load Power Factor (assumed standard **0.8 lagging**) and multiplied by the safety cushion factor: VA = (Watts / 0.8) x Safety Factor.
• Battery Sizing (AH): Accounts for inverter conversion losses (~10% thermal loss, 90% efficiency) and chemistry discharge limits to prevent cell damage: AH = (Watts x Hours) / (System Volts x DoD% x 0.90 Efficiency).
• Depth of Discharge (DoD): Lead-acid batteries should not be discharged completely. Discharging standard tubular cells beyond **70%** severely reduces their overall cycle life.