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Backup Time Formula:
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The Battery Backup Time Calculator estimates how long a battery can power a specific load, taking into account the battery's energy capacity and the system's efficiency.
The calculator uses the backup time formula:
Where:
Explanation: The formula calculates how long a battery can sustain a given load by dividing the battery's total energy by the load's power consumption, then adjusting for system efficiency losses.
Details: Accurate backup time calculation is crucial for designing reliable power backup systems, ensuring uninterrupted operation during power outages, and proper sizing of battery systems for various applications.
Tips: Enter battery capacity in watt-hours (Wh), load power consumption in watts (W), and system efficiency as a decimal between 0 and 1. All values must be positive numbers.
Q1: What is watt-hour (Wh) capacity?
A: Watt-hour is a unit of energy that represents the amount of energy a battery can deliver. It's calculated as battery voltage multiplied by amp-hour rating.
Q2: Why include efficiency in the calculation?
A: Efficiency accounts for energy losses in the system, including inverter losses, wiring losses, and battery internal resistance. Typical efficiencies range from 0.8 to 0.95.
Q3: How accurate is this calculation?
A: This provides an estimate. Actual backup time may vary based on battery age, temperature, discharge rate, and other factors.
Q4: Can this be used for all battery types?
A: Yes, the formula works for lead-acid, lithium-ion, and other battery types, though efficiency values may differ.
Q5: What affects battery backup time?
A: Backup time is affected by battery capacity, load power, system efficiency, battery age, temperature, and discharge rate.