In electrical engineering, power ratings are a metric associated with electrical equipment. All electrical equipment is rated based on the maximum power they can safely consume, generate, or transfer. You can find this on a nameplate with the operation voltage/power.
Depending on this function, they are rated in different units, with the expected kVA to avoid pushing too much current. Uses the apparent power .
- Consumption: motors, heaters, lamps, rated in kilowatts.
- Generation: generators, alternators, rated in kilo-volt-amperes
- Transfer: transformers are rated in kVA
This is the result of safety considerations for the users, the equipment, and the surrounding infrastructure. For example, for generators, we don’t know what the power factor on the load is, so a safe kVA is specified so that the generator doesn’t explode.