If a 5 kVA UPS supports a critical load of 4 kW, what is the approximate battery hold-up time during a power outage?

To determine the approximate battery hold-up time for a UPS (Uninterruptible Power Supply) during a power outage, one must consider both the power rating of the UPS and the critical load it supports. A 5 kVA UPS that supports a 4 kW load indicates that the UPS has a power factor, typically close to 1 (in this case, it would be 4 kW / 5 kVA = 0.8).

The hold-up time of the battery can be calculated based on its capacity (measured in Ampere-hours, Ah) and the load it supports. Assuming we have typical values for battery capacity for a 5 kVA UPS, let's say it has a battery capacity that can sustain 4 kW for a certain amount of time. If the UPS typically has a battery capacity of around 4-5 Ah at high power, we can estimate that it would provide power for a more extended period, such as 10-15 minutes under this specific load.

The correct answer indicates around 10 minutes as a reasonable hold-up time, which aligns with common specifications for battery life in similar UPS systems. Factors such as battery age, health, and load conditions can also affect actual times, but