Ans. Graphically, that is to say by means of a curve plotted on coordinate paper of which ordinates represent load values and the corresponding abscissæ time values, as in the accompanying curves.
What is the nature of a power load?
Ans. Where electricity is supplied for power purposes to a number of factories, the load is fairly steady, dropping, of course, during meal hours. In the case of traction, the average value of the load is fairly steady but there are momentarily violent fluctuations due to starting cars or trains.
Fig. 2,718.—Load curve for one year.
Ques. What is the peak load?
Ans. The maximum load which has to be carried by the station at any time of day or night as shown by the highest point of the load curve.
Ques. Define the load factor.
Ans. The machinery of the station evidently must be large enough to carry the peak load, and therefore considerably in excess of that required for the average demand. The ratio of the average to the maximum load is called the load factor.