The load limit of the ADG is specified in which unit?

• A. kVA
• B. Watt
• C. kW
• D. A

Answer: (A)

The important idea is that the capacity of an emergency generator is described by apparent power, not just real power. The load limit of the ADG is given in kilovolt-amperes (kVA) because kVA represents the maximum voltage multiplied by current the generator can supply, regardless of the load’s power factor. Real power, measured in kilowatts (kW), depends on the power factor of the connected load, so it can vary even if the apparent power capacity stays the same. Amperes alone don’t indicate how much total power the generator can deliver, and watts alone don’t account for the voltage-current interaction. So the correct unit to specify the ADG’s load limit is kVA.