Find out how to choose inverter, how much inverter capacity, which battery for your inverter and more when you buy inverter and battery for your home.
Planning to buy a new inverter, battery, inverter battery combo or upgrade the old one? Whatever the reason, it is very important to understand the right inverter and battery for your home. Want to choose the best configuration? You would need answers to the following questions:
- What is your Power requirement?
- What VA rating will you need basis your requirement?
- What will be the right battery for your inverter?
- What do we want? - Single Battery or Double Battery?
- Which Battery plate type is required?
- Consult with Technical Person ?
- Let Us First Understand Your Power Requirement
One of the most important thing that you must know before buying an inverter is your “power requirement”. In simple words- what all home appliances (like lights, fans, televisions, or any other appliances) you will run at the time of power cut. Power requirement is an addition of the power consumed by various electrical home appliances.
How to decide inverter capacity for home?
Suppose you want 3 Fans, 3 Tube lights, 8 LED lights, 1 television & 1 refrigerator to operate at the time of power failure. The power consumed by these items will be total of the power consumed by these individually:
1 Fan – 70 Watts
1 tube light – 40 watts
1 led light – 7 watts
1 led television – 70 watts
1 Refrigerator - 140 Watt
Therefore your total power requirement is (3*70 +3*40 +8* 7 + 1*70+ 1*140) = 596 watts
- Find the VA Rating of the Inverter You Need
VA stands for Volt ampere rating. It is the voltage and current supplied by the inverter to the equipment. Your appliances need more VA than the power requirement in Watts due to the nature of the devices. The ratio is called Power factor.
Hence Power supplied (or VA rating of inverter) = Power requirement (power consumed by equipment in watts) / Power factor.
Usually, at homes, power factor ranges from 0.65 - 0.8, taking 0.7 for the calculations,
Power of inverter (VA) = 596/0.7 = 851 VA
So an inverter with 900 VA will be the right choice for your home
- Know the Battery Your Inverter Needs
The performance of an inverter largely depends on the battery. Battery stores the energy needed to run your appliances during power cut. The next big question is “how much back up will an inverter provide?” or for “how many hours it can run all of your appliances?”. This is determined by battery capacity. It is expressed in Ah (Ampere Hours).
Luminous batteries are available from 60 Ah - 220 Ah, so how will you finalize which one do you need? To find this out let’s do a reverse calculation. Consider that you need a battery that provides back up for 2 hours for running appliances of load 851 VA (596 W).
Battery capacity = Power requirement (in VA) * Back up hours (in hrs) / Battery Voltage (in volts)
For lead acid battery, battery voltage = 12 V.
Battery Capacity = (851 * 2) / 12 = 142 Ah
In reality battery performance degrades with usage, so you are recommended to buy 5-10% higher capacity battery.
Therefore a battery with a capacity of 150 Ah will work for you.
So if you want to run 3 Fans, 3 Tube lights, 8 LED lights 1 television & 1 refrigerator for 2 hours during power failure you would need 900 VA inverter and 150 Ah battery.
- Single Battery or Double Battery
Now suppose your power back up requirement is 4 hrs for the same power load.
Battery Capacity required = (851*4) / 12 = 284 Ah ~ 300Ah
Since batteries are available between 60-200Ah, you will need 2 battery of 150Ah (in series) to provide 300 Ah. Two batteries together create 24 V output, hence you need to choose inverter which supports 24V input.
- Battery Plate Type
Lead acid batteries come in flat plates or tubular (rod shaped) plates.
Flat Plate or Tubular batteries come in small height containers, and are suitable for low power cut areas as their designed cycle life is low.
Tubular batteries come in small as well as tall containers, they typically have longer design life, suitable for all areas. Due to the longer life, they are replacing flat plate batteries in inverter battery applications.
Plates should be constructed from highly pure lead alloy with high-pressure casting machines to ensure low maintenance and long life.
- Consult with Technical Person
Finally, you can consult with technical person or shop owners. They can assist very well as you need inverter and battery for your home
