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Important terms and definitions:y Connected load:

It is the combined continuous rating of all the

receiving apparatus on consumers premises.If a consumer has connections for 3 lamps of 40

watts each, and power point of 500W forrefrigerator and TV consuming 60W, then the totalconnected load of the consumer = 3x40+500+60 =680W

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yMaximum Load /demand: It is the maximumload which is used a consumer at any time. It can

be less than or equal to connected load.yDemand factor: It is the ratio of maximum load

to consumer load.

y Av

erage load= energy consumed in 24 hrsy Load factor = average load / Peak load

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Plant Capacity factor (Plant load factor)= actual energy produced in kWh

Rated capacity of the plant= E/Cxt= Peak load x load factor/plant capacity= Use factor x load factor

Where, E = Energy produced in kWhC = capacity of the plant in kWt = Total number of hours in given period.

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y Utilization factor= Maximum load_____

rated capacity of the plant

y Reserve factor = ___Load factor___

capacity factory Diversity factor= sum of individual maximum demand

actual peak load of the system

y Plant use factor = actual energy produced in given time period

maximum possible energy produced by the plant

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Load curvey It is a graphical representation which show the

power demands for every instant during a certaintime period.

y It is drawn between load in kW and time in hours.y If it is plotted for 1 hr, it is called hourly load curve

and if the time is considered of 24 hours, then it iscalled daily load curve. When it is plotted for one

year then it is called annual load curve.y The area under the load curve represents the

energy generted in the period considered.

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Load curve

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Load duration curve

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Types of loadsy Residential load

y Commercial load

y Industrial loady Municipal load

y Irrigation load

y Traction load