UPS Sizing (Data Center) Calculator

Size UPS modules and battery banks for data center backup power with redundancy and runtime requirements.

IT load (kW)

UPS efficiency (%)

Battery runtime (min)

Redundancy Mode

Power factor

Depth of discharge (%)

DC bus voltage (V)

Tab to move between fields

UPS modules needed

Module size (kVA each)100

Total UPS capacity (kVA)400

IT load (kVA)222.22

Battery capacity (kWh)65.79

Battery (Ah)137.1

UPS losses (kW)12.77

Battery footprint (ft²)197

Total Ups Kw360

Ah Per String137.06

Battery Weight (lbs)3,626.64

How to Use This Calculator

Enter total critical IT load in kW.
Set UPS efficiency and desired runtime in minutes.
Input battery string voltage and design temperature.
Review the required UPS kVA rating and battery capacity in amp-hours.
Add N+1 module redundancy to ensure maintenance without loss of critical protection.

How the result changes with IT load (kW)

IT load (kW): Total critical IT load the UPS must protect.
UPS efficiency (%): UPS conversion efficiency. Modern online UPS: 94-97%.
Battery runtime (min): Desired battery runtime. Typical: 5-15 min (bridge to generator).
Redundancy Mode: Select UPS redundancy configuration
Power factor: UPS output power factor. Modern UPS: 0.9-1.0, legacy: 0.8.
Depth of discharge (%): Battery depth of discharge. VRLA: 80%, Li-ion: 80-90%.
DC bus voltage (V): UPS internal DC bus voltage. Common: 384V, 480V, 600V.

UPS modules needed: Number of UPS modules for the selected redundancy.
Module size (kVA each): Rating of each UPS module.
Total UPS capacity (kVA): Combined UPS capacity of all modules.
IT load (kVA): IT load converted to kVA at the specified power factor.
Battery capacity (kWh): Required battery energy storage accounting for efficiency and DOD.
Battery (Ah): Battery amp-hour capacity at DC bus voltage.
UPS losses (kW): Power lost to UPS conversion inefficiency.
Battery footprint (ft²): Estimated floor space for VRLA battery cabinets.

Identify Input Parameters
4 parameters
IT load (kW) = 200, UPS efficiency (%) = 94, Battery runtime (min) = 15, Redundancy Mode = 1 = 7 input(s) provided
Calculate UPS modules needed
4 = 4
Calculate Module size
100 = 100
Calculate Total UPS capacity
Total UPS capacity = numModules * moduleSizeKva
400 = 400