If you’re getting an Inverter, choosing the right battery capacity is super important. The right battery capacity means you get exactly the power you need, without the need for any form of overpaying, while also getting sufficient backup for your needs.
Undersized batteries can come up with problems like voltage drop, shortened backup time, premature battery death and a lot of other problems, while an oversized battery can result in issues like chronic undercharging, long charging times, wasted energy, and higher costs.
Which is why knowing how to calculate tubular battery capacity is a really important skill in today’s day and age. Here, Livfast has a quick and easy guide on tubular battery capacity calculation.
What is Tubular Battery Capacity?
Before you learn to calculate tubular battery backup time, you need to understand what tubular battery capacity is. To put it simply, it is measured with a number called the Amphere-Hour rating. But what is it?
Ampere hours, or Ah, is the amount of energy charge in a battery that lets 1 ampere of current flow for one hour. In other words, 1 Ah is the rating that shows storage capacity or how much current it can supply. The unit is a good way to figure out how much energy a rechargeable battery or deep-cycle battery can hold.
The following is how Ah is written in math:
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Amp hour (Ah) = Current (I) times Discharge time (T)
You can use this example: a battery that pulls 30 amps (A) and is depleted in 30 minutes:
30 A is the current.
Time to discharge: 30 minutes (0.5 hours)
Ampere hour is 30 times 0.5, or 15 Ah for one hour.
Understanding Tubular Battery Charging Voltage
Before selecting or sizing a tubular battery, it’s important to understand the tubular battery charging voltage chart. This is because incorrect battery charging habits are often one of the most common reasons for poor backup performance and reduced battery life. Tubular batteries require specific voltage ranges during different charging stages to ensure efficient charging without overcharging or undercharging. Charging voltage determines how safely and completely the battery is recharged after a power cut and provides consistent power during the next power cut.
How to Calculate the Tubular Battery Capacity?
Now, let’s take a look at how we can calculate the tubular battery capacity, and for that, we’ll take a structured approach:
Key Factors Required to Calculate Tubular Battery Capacity
Firstly, these are the key factors you need to keep in mind when calculating tubular battery capacity, they are:
- Total Load in Watts: The total power consumption of your house
- Required Backup Time: How much backup time do you actually need
- Battery Voltage (12V / 24V): Single battery vs multiple batteries
- Inverter and Battery Efficiency: Ensure 80% efficiency to make the calculation seamless.
Formula to Calculate Tubular Battery Capacity
Now, you need to know the formula of how to calculate tubular battery capacity:
Battery Ah = (Total Load in Watts × Backup Hours) ÷ (Battery Voltage × Efficiency)
Step-by-Step Tubular Battery Capacity Calculation
Step | Description | Calculation | Result |
Step 1 | Calculate total connected load | Fans (2 × 75W) = 150WLights (4 × 15W) = 60WTV = 120WWi-Fi Router = 20WMiscellaneous = 175W | Total Load = 525W |
Step 2 | Multiply by the required backup time | 525W × 4 hours | 2100 Wh (watt-hours) |
Step 3 | Account for battery voltage and efficiency | 2100 ÷ (12V × 0.8 efficiency) | 218 Ah (approx.) |
Step 4 | Select the nearest higher battery capacity | Available options: 200Ah, 220Ah | Choose 220Ah battery |
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It’s always recommended to round up the figure of your required battery if it’s a non-rounded number. This is because it will ensure proper reliability, and your tubular battery backup time will be reliable during power outages.
Practical Examples for Home and Solar Use
Example | Typical Load | Backup Needed | How the Calculation Works | Recommended Battery Capacity |
Example 1: Medium Home Inverter Setup | 400–450W (fans, lights, TV, Wi-Fi) | 3–4 hours | A 400–450W load running for 3–4 hours needs roughly 1200–1800Wh. Dividing this by 12V and allowing for inverter losses gives a practical requirement of around 150–180Ah. | 150Ah to 180Ah tubular battery – ideal for most 2–3 BHK homes |
Example 2: Heavy Load or Long Backup Requirement | 700–1000W (fridge, multiple fans, TV, lights) | 4–6 hours | High loads drain batteries faster, so a single battery struggles. Even if the math shows 250–300Ah, it’s safer and healthier to split this across multiple batteries. | Two 150Ah or two 180Ah batteries (24V system) for better performance and longer life |
Example 3: Solar Tubular Battery Calculation | 300–500W average solar load | Day–night cycle (6–10 hours) | Solar batteries are discharged slowly over many hours. That’s why C10-rated capacity matters more than label Ah. The battery must store enough energy during the day to last through the night. | 150Ah–220Ah C10 solar tubular battery, depending on night usage |
Conclusion
Now, you must be aware that knowing how to calculate tubular battery capacity is quite important; it allows you to make a more informed choice. Now, sometimes, you not only need reliability, but speed as well, and this is why you should go with Livfast, as you get a 25% higher charging speed than the competitors in the market. Our inverters and batteries come with:
- 25% Faster Charging
- Low Voltage Performance
- 25% Longer Backup
- Consistent Performance