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Key Services Generation 65
KEY SERVICES GENERATION
For intermediate operating conditions, when, for example, certain process or service
machinery is required, but production is shut down or the level of production does
not require the running of main generators, key services or submain generators may
be run. These would allow all the utilities, such as accommodation ventilation and
cooling systems, plus the statutory services, to be operated without the need to run
the main generators at inefficient power levels. Key service generators can also be
used to provide peak load power, particularly during a planned outage of a main
generator. It is best, however, to avoid running machines of dissimilar size in parallel
whenever possible, as the shorter time constants usually associated with the smaller
machine tend to cause it to react more quickly to step increases in load and this leads
to system stability problems.
Emergency generation is covered in PART 2 Chapter 3.
