How do I calculate UPS Sizing & Runtime?

To calculate UPS Sizing & Runtime: Enter Critical load, Load power factor, UPS efficiency and other values. Click Calculate. INDUGRID computes the result instantly using the formula: kVA_UPS = kW_load / (PF x eta) | t = (C_Ah x V_bat x eta_inv) / (P_load x 1000) x 60. No registration required.

What units does the UPS Sizing & Runtime calculator use?

The UPS Sizing & Runtime calculator uses the following units: kW, %, V, Ah. SI units are used by default.

Is the UPS Sizing & Runtime calculator free?

Yes. The INDUGRID UPS Sizing & Runtime calculator is completely free, requires no account or login, and works on desktop and mobile browsers.

Battery & DC Systems

UPS Sizing & Runtime

Size an Uninterruptible Power Supply for critical loads and calculate backup runtime from battery capacity.

Units:

in LinkedIn

💡Size UPS at 60-80% of rated kVA to allow for crest factor and future growth. Online double-conversion UPS: 90-95% efficient. Always verify battery replacement cycle (typically 3-5 years for VRLA).

kVA_UPS = kW_load / (PF x eta) | t = (C_Ah x V_bat x eta_inv) / (P_load x 1000) x 60

Input

Critical load iTotal power of loads that must be backed up in kW.

Load power factor iServers/IT: 0.9-0.99. Mixed loads: 0.7-0.85.

UPS efficiency iOnline double-conversion: 88-96%. Line-interactive: 95-99%.

Battery string voltage iTotal battery string voltage. Typical: 96V, 144V, 192V, 240V DC.

Battery capacity iBattery capacity in Ah at C10 rate.

Inverter efficiency iDC to AC conversion efficiency. Typical: 88-96%.

Result

Required UPS size [kVA] —

Recommended UPS (70% load) [kVA] —

Backup runtime [min] —

Battery energy [kWh] —