Usually, the Power of the diesel generator set will be clearly marked on the nameplate of the unit, but the nominal output Power of each manufacturer is different, which is divided into: standby Power (Standly Power), common power (Prime Power) and Consecution power (Consecution Power).

1. Standby power: defined as the maximum power of the generator set that can run continuously for 300h and up to 500 working hours per year between the specified maintenance cycles and under the specified environmental conditions. It is equivalent to the time-limited operating power (LTP) in national and ISO standards. Generally suitable for communication, buildings and other load changes more accidental emergency conditions.

2.  commonly used power:

   defined as the maximum power existing in a variable power sequence between the specified maintenance cycles and under the specified environmental conditions, the number of possible hours of operation per year is not limited, which is equivalent to the basic power (PRP) in national standards and ISO standards. Generally applicable to factories, mines, military and other load changes less frequent operating conditions.

3. Continuous power: defined as the maximum power existing in a constant power sequence between specified maintenance cycles and under specified environmental conditions, the possible time of operation per year is not limited. It is equivalent to the continuous power (COP) in national and ISO standards. It is generally suitable for continuous operating conditions with minimal load changes as a power station or connected to the grid.

   
   

Diesel generator power can not be compared with the mains, because the diesel generator is the mechanical energy of the diesel engine into electrical energy, the diesel engine in the process of work is attenuated, the relevant power definition is listed as follows:

1, diesel generator emergency standby power (ESP): 

under the agreed operating conditions and manufacturer's regulations for maintenance, in the case of mains interruption or under experimental conditions, the generator set with variable load operation and annual operation time up to 200h maximum power. The average power output allowed during a 24h operating cycle should not exceed 70%ESP, unless otherwise agreed with the manufacturer.

2, diesel generator limited operating power (LTP): 

under the agreed operating conditions and in accordance with the manufacturer's regulations for maintenance, the generator set can run for 500h per year maximum power. The maximum operating time is 500h per year at 100% time limit power.

3, diesel generator basic power (PRP): 

under the agreed operating conditions and in accordance with the manufacturer's regulations for maintenance, the generator set with variable load continuous line and the number of annual operating hours is not limited to the maximum power. The average power output (Ppp) of the operation during the 24h operation cycle shall not exceed 70% of the PRP, unless otherwise agreed with the engine mechanism. Continuous power COP should be used in applications where the allowable average power output Ppp is higher than the specified value

4, diesel generator continuous power (COP): 

under the agreed operating conditions and in accordance with the manufacturer's regulations for maintenance, the generator set at a constant load continuous line of annual operating hours of unlimited maximum power

The standard also provides for the on-site conditions of the operation of the generator set: the on-site conditions are determined by the user, and in the case of unknown site conditions without other provisions, the following rated site conditions should be adopted

1, absolute atmospheric pressure: 89.9kPa (or altitude of 1000m).

2, ambient temperature: 40°C

3. Relative humidity: 60%