Sizing, ratings and selection notes for diesel generator sets.
A sound-attenuated canopy typically removes 20 to 25 dB(A), adds 1.5 to 2 m of length and 10 to 20 per cent of transport weight. Compare the choice on the permitted sound level, the space and the access route.
Prime power carries a variable load for unlimited hours with a 10 per cent overload for one hour in twelve; standby power is declared for the duration of a mains failure with no overload allowance. A 500 kVA set is two different machines depending on the rating.
Convert the running load to kVA at 0.8 power factor, add the starting demand of the largest motor, then add 10 to 20 per cent margin. A 320 kW load with one 55 kW direct-on-line motor needs about 800 kVA.
