How are generators sized?
Generators are sized in several different ways depending on the requirements of the site and load to be covered. For example some customers may require that the generator provides backup for the entire site while others may only require ‘essential’ loads to be generator backed. It is also necessary to consider the type of load that will be applied to the unit. For example, UPS loads have some harmonic content (especially older UPS’s) and the generator must be sized to cope with this type of load.
Motors and pumps are another load that will affect the performance of the generator during starting. Another aspect to consider is the nature of the engine chosen. Some turbo-charged engines have a relatively low initial load step capability – it is sometimes necessary to oversize the unit to cope with the required site load.
Careful thought of which loads to apply and whether to stagger the re-application of the loads can make a significant difference to the overall cost of the installation.
- AURORA Generators