How to choose Inverters and Batteries
Ms.S. Keerthana
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ABOUT
In this article, we will be talking about the inverters which we get installed in our home by local dealers. So there may be a lot of questions regarding the type of inverter and whether it is enough to power all necessary appliances in your home and so on. So we are here to let you understand how this is all done and why is it important to make a rough calculation beforehand and in future, you will be aware of the process involved and there will be transparency when you will interact with local dealers about the components used at your place.
Calculating the Power needs:
Before getting an inverter at your place we have to calculate the total power demand which will be required in order to run certain appliances using the inverter during power cuts. We are going to write down the power consumption of certain components which will be a standard value and in real work scenario there may be a chance of slight variation
» 1 Fan- 70-80 W
» 1 Tube Light- 40-50W
» CFL – 25W
» LED Bulbs- 15W
» LED TV- 60-100W
» Mobile Chargers-7W
* Total Power consumed=3*70+1*40+3*25+2*15+1*100+1*7= 462W
» let us assume approximately we require 500W of power for running the house during the power cut.
Choosing the Inverter
» Here comes the tricky part, there are many types of inverter available like Pure Sinewave, Squarewave, and Modified Sinewave. The best inverter is Pure Sinewave and it is quite costly but it is worth the price. Squarewave is considered to be a cheap alternative but the power quality is not that great and produces humming noise in inverters which does not sound cool and there is a modified sine wave in between in this case the square wave is modified to output as a sinewave using power electronic circuit. It is totally up to you and you can get the inverter of your wish. We discussed the types and now we have to choose the rating of the inverter.
» The Inverter is rated in VA that is why we need VA value of our power demand. We know that our power demand is 500W and we have something called power factor which is not always in unity and let us assume that the power factor is 0.7 for our inverter.
» VA value needed= Power Demand/Power Factor = 500/0.7 = 714VA
» Now you just can’t simply go to the inverter shop and ask for an exact rating. So the inverter is rated mostly in round figures like 700VA,800VA,900VA,1KVA, and so on.800VA will be ok for our load demand but for future-proofing, we can go for a 900VA unit.
Choosing the Battery:
The backup time that we need decides the rating of our Battery. Mostly we use lead-acid batteries because it needs less maintenance and it is cost-effective. There are certain types in inverter batteries as well depending on the construction. Tubular batteries are the best and recently it is gaining popularity. The Batteries are rated in Ampere Hours which is AH in short. This means the battery can deliver that much amount of Current(A) in an hour. Mostly 12V Batteries are used for our homes and it is widely used. let us find the AH capacity we need to run our house for 5 Hours during Power Cut.
» We know the VA need of our home which is 714 and we need to run the load for 5 hours so we will multiply both factors then we will get the total power needs for 5 Hours.
* 714*5= 3570
» Now we divide this value by 12 which is the battery voltage of our inverter battery and by doing this we will get to know the Ah needs for our load demand
* 3570/12=297AH
» This is our calculation and we need a 300AH battery. I’ll connect 2 * 200AH batteries in parallel to achieve the 400AH capacity for more backup time.
We have included loads like TV and 3 Fans and it is running for five hours and that is why the demand is also high but most of the time we don’t run TV during power cuts and 200AH battery is more than enough for normal household needs. For explaining purpose I have included loads like TV and more number of devices to give the real-life scenario.
» I hope that you have gained some information related to Inverters and Batteries and now you can able to calculate and get your desired components from trusted brands for your home Inverter System.
