UPS Sizing Calculation Excel Sheet

What is UPS?

An Uninterrupted Power Supply or Uninterrupted Power Source (UPS) is an electrical apparatus which provides emergency power backup to vital electric equipment like computers, servers etc. when the main power source fails without any prior notice.

A UPS differs from the conventional emergency power sources like standby generators and protects from unexpected main power failures by providing nearly instantaneous uninterrupted power, usually stored in batteries or supercapacitors.

The on-battery runtime of most UPS is low but sufficient to start a standby generator in the mean time, hence preventing the equipment from shutdown.

UPS is mostly used to protect computers, data centers and telecommunication, hospital equipment from power disruption to avoid any data loss, injury, fatalities, and business loss etc. 

Sizing a proper UPS is critical when designing such emergency backup systems to avoid any loss or accident in case of power failure. Below is an excel sheet which can be used to properly size a UPS for your home, office or construction project.

To get the Ampere of the the battery bank required:

1. Enter electrical load details
2. Enter Battery Bank's Voltage
3. Enter Reserve Day: (How many days Do you want to get Power from battery Banks)
4. Enter Loose Connection/Wire Loss Factor
5. Enter Battery Efficiency
6. Battery Aging
7. Depth of Discharge:(DOD)
8. Battery Operating temperature

• The Result will be as follow:

1. Type of Connection For Batteries 
2. Batteries Connection type 
3. Each Battery Voltage 
4. Number of String for Battery Bank 
5. Total Amp.Hr of Each String 
6. Total No of Battery in Each String

 

To get the Size of Invertor:

1. Calculate Additional Future Load 
2. Enter the Efficiency of Invertor

With this excel sheet calculator you will be able to make sizing and selection for UPS battery and the inverter.

Download UPS Sizing Calculation Excel Sheet