1. What is Battery Backup Run Time?

The Battery Backup Run Time calculation determines how long a battery can power a load (MPH) based on its watt-hour capacity and the power consumption of the load.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• Backup Wh — Total energy capacity of the battery in watt-hours
• MPH Load W — Power consumption of the load in watts

Explanation: This formula divides the total energy available by the rate of energy consumption to determine how long the battery can last.

3. Importance of Run Time Calculation

Details: Accurate run time estimation is crucial for designing backup power systems, ensuring uninterrupted power supply, and selecting appropriate battery sizes.

4. Using the Calculator

Tips: Enter the battery's watt-hour capacity and the load's power consumption in watts. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between Wh and Ah?
A: Watt-hours (Wh) measure energy capacity, while amp-hours (Ah) measure charge capacity. Wh = Ah × Voltage.

Q2: How do I convert battery mAh to Wh?
A: First convert mAh to Ah (divide by 1000), then multiply by battery voltage: Wh = (mAh/1000) × V.

Q3: Does this account for battery efficiency?
A: No, this is theoretical maximum. Real-world results may be 10-30% less due to efficiency losses.

Q4: What affects actual run time?
A: Temperature, discharge rate, battery age, and inverter efficiency can all impact actual run time.

Q5: How can I increase run time?
A: Use a larger battery (higher Wh), reduce load (lower W), or add more batteries in parallel.