Battery backup duration:
Here we have an equation to find the battery life on load
Time(in Hrs) = (Battery Voltage (In volts) * Battery Capacity (in Ah)*efficiency of inverter)/ Load (in VA)
Let us have a sample calculation:
Battery voltage = 12 Volts
Battery Capacity = 150 Ah
You want 3 Fans, 4 Tube lights, 2 CFL & 1 Television to operate at the time of power failure.
Therefore your total power requirement is (3*70 +4*40 + 2*18 + 150) = 556 watts
Inverter efficiency = 70%= 0.7
Backup Time = 12 * 150*0.7/556= 2.26 Hrs (Approx)
If you want more backup time then you need to connect another battery in series.
If you decrease the load, definitely the backup time will be more for the same above ratings of the inverter and battery.
Following are some of the inverter brands that provide you with different types of inverters:
In short the following should be taken into consideration before\after purchasing inverter and battery:
- Calculating the power consumption of home as per the daily usage.
- As per the power consumption, calculate the VA and Ah ratings of inverter and battery respectively.
- Make sure the bill contains the details of the warranty period.
- After sales support (Go for a dealer or brand who offers onsite warranty repair and maintenance).
- Place the Battery and Inverter near to some window.
- Check the distilled water levels of the battery for tubular batteries at regular intervals.
Check my previous post on Different types of Inverters and Batteries
