2.3.2.4

Influencing Factors. The number of individual loads in a group and

their load factors influence the individual load coincidence factor. The

coincidence factors in Table 8 apply for groups of l00 or more individual

loads. These coincidence factors can also be used for groups of as few as 30

to 50 individual loads if their load factor is 0.30 or greater. For areas of

fewer individual loads, the mathematical relationship from IEEE Technical

Paper 45-116 provides a basis for estimating the connected coincidence factor

as shown by the following equation:

2.3.2.5

Individual Loads. The coincidence factors in Table 8 are based on

the individual loads in a group being substantially the same size. If a

single load or small group of loads in an area represents a substantial

percentage of overall load, the coincidence factors as given in Table 8 will

no longer apply. With an individual load, increase the coincidence factor to

a value commensurate with its effect on the overall area load. This is not

in addition to, but in place of, the normal coincidence factor. Determine

this value by considering intergroup coincidence factors given in paragraph

2.3.2.6. (An example of facility Navy code 211-70 is presented in Table 7.)

For a small group, determine the coincidence peak load, and to this apply

the appropriate intergroup coincidence factor to obtain the coincidence peak

load for the area.

2.3.2.6

Groups of Loads or Areas. Where groups of loads within an area, or

areas within a facility are combined, an additional intergroup coincidence

factor will exist. For loads of a similar nature, the intergroup coincidence

factor should be in the range 0.93 to 1.00. If loads of a varying nature

(evening loads and daytime loads) are combined, the intergroup coincidence

factor should be in the range of 0.70 to 1.00. The lower values will occur

when the magnitudes of the loads are nearly balanced, and the higher ones

when the combined load is predominantly one type.

2.3.3

Load growth. In addition to planned expansion, increased

application of electric equipment will generate an increase in load. When

sizing components, such as transformers or feeders for the area system,

consider possible load growth in addition to that included in the

determination of individual loads.

2.3.4

System Losses. Add distribution system losses to estimated area

demands.

For a good approximation, use 6 percent of the calculated maximum

demand.

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