1 files changed, 40 insertions, 0 deletions
diff --git a/3472/CH34/EX34.2/Example34_2.sce b/3472/CH34/EX34.2/Example34_2.sce
new file mode 100644
index 000000000..8d6402589
--- /dev/null
+++ b/3472/CH34/EX34.2/Example34_2.sce
@@ -0,0 +1,40 @@
+// 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 8: PROTECTION OF ALTERNATORS AND AC MOTORS
+
+// EXAMPLE : 8.2 :
+// Page number 624-625
+clear ; clc ; close ; // Clear the work space and console
+
+// Given data
+MVA = 20.0            // Generator rating(MVA)
+V = 11.0*10**3        // Generator voltage(V)
+ratio_CT = 1200.0/5   // Ratio of current transformer
+I_min_op = 0.75       // Minimum operating current of relay(A)
+R = 6.0               // Neutral point earthing resistance(ohm)
+
+// Calculations
+I_max_fault = ratio_CT*I_min_op       // Maximum fault current to operate relay(A)
+x = I_max_fault*3**0.5*100*R/V        // Unprotected portion for R = 6 ohm(%)
+R_1 = 3.0                             // Neutral point earthing resistance(ohm)
+x_1 = I_max_fault*3**0.5*100*R_1/V    // Unprotected portion for R = 3 ohm(%)
+R_3 = 12.0                            // Neutral point earthing resistance(ohm)
+x_3 = I_max_fault*3**0.5*100*R_3/V    // Unprotected portion for R = 12 ohm(%)
+
+// Results
+disp("PART III - EXAMPLE : 8.2 : SOLUTION :-")
+printf("\nUnprotected portion of each phase of the stator winding against earth fault, x = %.f percent", x)
+printf("\nEffect of varying neutral earthing resistance keeping relay operating current the same :")
+printf("\n (i)   R = 3 ohms")
+printf("\n       Unprotected portion = %.1f percent", x_1)
+printf("\n       Protected portion = %.1f percent", (100-x_1))
+printf("\n (ii)  R = 6 ohms")
+printf("\n       Unprotected portion = %.f percent", x)
+printf("\n       Protected portion = %.f percent", (100-x))
+printf("\n (iii) R = 12 ohms")
+printf("\n       Unprotected portion = %.f percent", x_3)
+printf("\n       Protected portion = %.f percent", (100-x_3))