// A Texbook on POWER SYSTEM ENGINEERING // A.Chakrabarti, M.L.Soni, P.V.Gupta, U.S.Bhatnagar // DHANPAT RAI & Co. // SECOND EDITION // PART III : SWITCHGEAR AND PROTECTION // CHAPTER 6: CIRCUIT BREAKER // EXAMPLE : 6.6 : // Page number 567 clear ; clc ; close ; // Clear the work space and console // Given data I = 1200.0 // Rated normal current(A) MVA = 1500.0 // Rated MVA kV = 33.0 // Voltage(kV) // Calculations I_breaking = MVA/(3**0.5*kV) // Rated symmetrical breaking current(kA) I_making = I_breaking*2.55 // Rated making current(kA) I_short = I_breaking // Short-time rating(kA) // Results disp("PART III - EXAMPLE : 6.6 : SOLUTION :-") printf("\nRated normal current = %.f A", I) printf("\nBreaking current = %.2f kA (rms)", I_breaking) printf("\nMaking current = %.f kA", I_making) printf("\nShort-time rating = %.2f kA for 3 secs", I_short)