Testing AC generator on a Unity power factor (Resistive Load)
The generator may not be rated for 400 kW, only 400 kVA &amp; 320 kW at 0.8 pf or 320 kVA &amp; 320 kW at 1.0 pf. The generator may be limited by the current that it can carry and the engine may only be rated to produce 320 kW. There are lots of loads that are lower than 1.p pf. For those loads a generator that is rated for 400 kVA and an engine that is rated to produce 400 kW would have an engine that is larger than necessary and cost more than necessary. If you know that the load pf is 1.0, it would be better to buy a generator that is rated 400 kVA at 1.0 pf.