Planning on buying a new inverter, or upgrade the old one? Whatever the case, 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 and VA rating?
- What will be the right battery for your inverter?
- What kind of inverter is suitable?
- Which Battery plate type is required?
Inverter Power requirement and VA rating
Once you are sure you need an inverter, the first thing to take into consideration is your power requirement.
For example your typical load might be 1 TV set, 1 decoder, 1 DVD player, 1 Fan, 1 Laptop and 3 light bulbs.Next you would need the power rating of each of the load device which is usually at the back or in the device manual.
The load rating for the above device could be
- 1 TV set(90w)
- 1 decoder(25w)
- 1 DVD player(40w)
- 1 Fan(70w)
- 1 Laptop(20w)
- 3 light points(90w)
- Total rating=335w
The next step is to get a VA equivalent of the power, which if we assume a power factor of 0.8 gives 418 VA (i.e. 335/0.8)
After calculating your total load, the next step is to derate the inverter to create some allowance for flexibility and to ensure it does not over work itself.
To derate, just multiply your total load by 2. In the example above 2 x 418 = 836VA. So, you will buy an inverter with a power rating of 900VA or higher.
The aim of derating is to ensure that your inverter does not operate at full-load or near full-load, which will ensure the longevity of the device.
What will be the right battery for your inverter?
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).
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 836 VA .
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 1 TV set, 1 decoder, 1 DVD player, 1 Fan, 1 Laptop and 3 light bulbs for 2 hours during power failure you would need 900 VA inverter and 150 Ah battery.
The best battery for your inverter is the SMF deep cycle inverter battery. SMF stands for Sealed, Maintenance Free. Though you can use the normal car battery, but they emit poisonous fumes which could have long term impact on your health. This means an SMF battery can be installed indoors making them very convenient
What kind of inverter is suitable?
Since square wave is rarely used because of their limitations Our choice is between the modified-square wave inverters and the pure sine wave inverters
Read Also: Types of Inverter Systems you need to know
The pure sine wave no doubt is more efficient but this doesn’t mean the other is deficient when used with home or office appliance.The choice is against cost as sine wave inverters are more costly.
Which Battery plate type is required?
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 are constructed from highly pure lead alloy with high-pressure casting machines to ensure low maintenance and long life.
Other Factors to consider
- Solar energy support and
- Installation cost.