Question

In: Electrical Engineering

1) . A factory load consists of the following : (i) an induction motor of 150...

1) . A factory load consists of the following :

(i) an induction motor of 150 h.p. (111·9 kW) with 0·7 p.f. lagging and 80% efficiency ;

(ii) a synchronous motor of 100 h.p. (74·6 kW) with 0·85 p.f. leading at 90% efficiency

(iii) a lighting load of 50 kW.

Find the annual electric charges if the tariff is Rs 100 per annum per kVA maximum demand plus 7 paise per kWh ; assuming the load to be steady throughout the year.

ANS[Rs 1,96,070]

2) . A hydro-electric plant has a catchment are of 120 square km. The available run off is 50% with annual rainfall of 100 cm. A head of 250 m is available on the average. Efficiency of the power plant is 70%. Find (i) average power produced (ii) capacity of the power plant. Assume a load factor of 0.6.

ANS [(i) 3266 kW (ii) 5443 kW]

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