ฺBattery calculation

HOW To calculation back up time for UPS

UPS Run Time/Battery Backup Time Calculator

Calculate the estimated run time or battery backup time of any uninterruptible power supply (UPS) using the device load (in watts), power factor, number of batteries, battery voltage.

This is description for cal. sheet.
1. kVa of UPS  ( calculation from load consumption)
2. Power factor of load (nominal assume 0.8 )
3. Inverter efficiency of ups (difference from each ups , nominal 0.94 )
4. end voltage of battery ( you can adjust , nominal 1.75-1.8)
5. No. of cells of battery ( depend dc bus of UPS )
6. Floating charge of battery ( depend on manual of battery)

If you fill all data in excel file you can see minimum require of current or watt of inverter and then you can choose battery Ah from discharge table of battery .

Example battery discharge table .