ISO 8528 provides a global standard for diesel and gas generator sets, including performance, ratings, and test methods.

The rating conditions mentioned (+25°C mASL; 30% relative humidity) are standard testing conditions to ensure consistency across tests and products.

PRP (Prime Power): This is the power a generator can supply continuously for an unlimited number of hours a year, with the expectation that the load will vary. The generator should not operate above 80% of this prime power rating over a 24 h period, and a 10% overload capacity is permitted only for governing purposes.

ESP (Emergency Standby Power): This defines the maximum power a generator can provide for up to 500 h per year, with no more than 300 h of those hours being continuous use. Maintenance must be performed as per the manufacturer's guidelines, and there is no overload capability beyond the ESP rating.

Voltage Ratings and Requests (50Hz 380V/400V/415V/440V/525V/660V and 60Hz 208V/220V/380V/400V/440V/460V/480V) are available upon request, indicating customization options for different regional requirements or specific application needs.