Make simple home power backup system using a battery
Hi Everyone, Today i am going explain you how to make a simple home power backup system using a battery. All Sri Lankan facing power issues there days and its is a hard time for every Sri Lankans specially in IT sector like me.
You need following items
- A battery (I am using a lead-acid battery but if you can use a deep cycle battery its great because when a lead-acid battery use its maximum, the normal charger cannot use for recharging / you may need to use a high charger in this case but the deep-cycle batteries are bit expensive and difficult to find a good one these days ) so make sure don’t utilize full battery if you are using a lead-acid battery. Normally there is a indicator in most of batteries we can identify it easily before drain the full battery. Invertors are also giving a warning when a battery reached its maximum.
- Battery charger (According to you battery capacity the charger need to select for example in I’m using a 20Amps charger to charge my 90A battery). Make sure to select a correct charger.
- Invertor – Invertor can convert 12V DC to 230V AC . Be careful when you select a invertor there are multiple type of invertors i have used modified sign wave invertor but if you can find a sign wave invertor its better (I am using 500VA invertor for my home use but be careful if you are plan to use more devices use more than 1000VA invertor)
Different Types of Inverters
Sine Wave, Modified Sine, and Square Wave – Say What?
![]() Sine Wave | ![]() Modified Sine Wave | ![]() Square Wave |
Reference : https://www.solar-electric.com/learning-center/inverter-basics-selection.html
How to setup ?
How to buy invertors and battery chargers in Sir Lanka to make home power backup system
You can online orders from daraz.lk but it will take time to receive because most of sellers are import invertors from other countries and there is a delay on these days you may wait like one month
But if you can go to pettah you can find invertors and battery chargers in the fist cross street to make a home power backup system
Shantha Electronics (Recommended – go inside the 59 market first floor in the left side 3rd shop as I remember both battery chargers and invertors available to but this shop)
Vickrama Plazza 59-1/5, First floor, First cross street, Colombo 11
Tel : 0112321615
or
Universal Electronics (Only invertors available – go inside the 88 athula market in the left side first shop)
88-A1, Electronic Plaza, Ground floor,
1st cross street, colombo 11,
Tel : 0112333581
Mobile : 0773723238
For the battery chargers there is a place in Nugegoda U. P. Electronics Enterprises they are manufacturing battery chargers (https://goo.gl/maps/6tsSZhswhh5p4JyN6) but you need to give an order and wait minimum two weeks to get it due to high demand on these days


Prize : Invertors and chargers are high demanded items in these days in Sri Lanka. I bought 500W invertor for 13000LKR and 20Amps Charger from shantha electronics for 13500 from shantha electronics few weeks ago to this post.
Lead-acid battery you can find easily from any battery shop the prices depends on battery capacity (Ah) and brand (90Ah lucas battery cost around 23000LKR)
Alternate option to invertor to make home power backup system
You can use UPS for this, you can remove the UPS existing battery and plug the external lead acid battery for this but I am not recommending this specially if you are using high Ah battery the USP may over heat and can damage (you may need to use some extra fans)

Warning !
Please keep away these electronics Items from kids and make sure you plug the devices to correct plus , minus ends , make sure you turn off the highly consumption electronic devices such as refrigerators, washing machines , Owens .. etc . And make sure to turn off the trip switch and main switch if you are going to plug the invertor output to your home use using a plug.
I am using 500W invertor and I can user 4 panel lights (12W) a table fan (45W) two laptops and a Wi-Fi router over 10 hours with 90Ah battery without any issue (I am turning off the all other devices when i plugin the invertor to home main circuit)