**Power Rating of Diesel Generator Sets**  

A diesel generator set is composed of a diesel engine and a synchronous alternator. 

The maximum permissible power output of the diesel engine is limited by the mechanical and thermal loads on its components. 

Therefore, the maximum power allowed for continuous operation must be specified, which is referred to as the ”rated power“.  

The diesel engine must not be operated beyond its rated power, as doing so can shorten its service life and potentially lead to accidents.  

(1) Rated Power of Diesel Engines

According to national standards, the rated power indicated on the nameplate of a diesel engine is categorized into the following four types:  

1) 15-Minute Power: The maximum power that the diesel engine is allowed to deliver for 15 minutes. This rating is used for applications 

    requiring short-term overload capability and rapid acceleration, such as diesel engines for automobiles and motorcycles.  

2) 1-Hour Power: The maximum effective power that the diesel engine is allowed to sustain for 1 hour. 

    This rating applies to diesel engines used in wheeled tractors, locomotives, ships, and similar applications.  

3) 12-Hour Power: The maximum effective power that the diesel engine is allowed to sustain for 12 hours, commonly referred to as the ”rated power“. 

    This rating is used for diesel engines in power station units and engineering machinery.  

4) Continuous Power: The maximum effective power that the diesel engine is allowed to sustain for prolonged, uninterrupted operation.