1. What is Battery Sizing Calculation?

The battery sizing calculation determines the required battery capacity (in ampere-hours) needed to power your UPS inverter for a specific duration. It ensures you select a battery with adequate capacity for your power backup needs.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• Inverter UPS W — Power consumption of your inverter in watts
• Backup h — Desired backup time in hours
• V — Battery voltage (typically 12V, 24V, or 48V)

Explanation: The formula calculates the total energy needed (watt-hours) and converts it to battery capacity (ampere-hours) based on the system voltage.

3. Importance of Proper Battery Sizing

Details: Correct battery sizing ensures your UPS system can provide adequate backup time without over-discharging batteries (which reduces lifespan) or overspending on unnecessarily large batteries.

4. Using the Calculator

Tips: Enter your inverter's wattage rating, desired backup time in hours, and battery bank voltage. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Should I add any safety margin to the calculated size?
A: Yes, it's recommended to add 20-25% extra capacity to account for battery aging and efficiency losses.

Q2: What's the difference between Ah and Wh?
A: Ampere-hours (Ah) measure charge capacity, while watt-hours (Wh) measure energy capacity. Wh = Ah × V.

Q3: How does battery type affect the calculation?
A: Lead-acid batteries should only be discharged to 50% capacity for long life, while lithium can often discharge to 80-90%.

Q4: What if my inverter has multiple batteries?
A: For batteries in parallel, add their Ah ratings. For series connections, the voltage adds while Ah stays the same.

Q5: How often should I recalculate my battery needs?
A: Re-evaluate whenever you add new equipment to your UPS load or when replacing batteries after 3-5 years.