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+// Example 5.18
+// Computation of (a) Locked rotor torque and the expected average in rush 
+// current (b) Repeat part (a) assuming motor is started at reduced voltage 
+// with 65% tap (c) In rush line current line current when starting at reduced 
+// voltage
+// Page No. 231
+
+clc;
+clear all;
+close;
+
+// Given data
+P=125;                 // Rated Voltage
+n=1141;                // Speed of machine
+hp=125;                // Horsepower rating of device 
+Vline=460;             // Line voltage
+ns=1200;               // Stator speed
+s=0.125;               // Slip
+ILS=683;               // Current at low side
+
+// (a) Locked rotor torque and the expected average in rush current
+Trated=P*5252/(n);                 // Rated torque
+Tlr=1.25*Trated;                   // Locked rotor torque
+kVA=(6.3+7.1)/2;
+Ilr=(kVA*1000*hp)/(Vline*sqrt(3)); // In-rush current
+
+// (b) Locked rotor torque and the expected average in rush current when motor 
+// is started at reduced voltage
+V2=0.65*Vline;                    // Voltage impressed across the stator
+I=Ilr*0.65;                       // Average in-rush current
+T2=Tlr*(V2/Vline)^2;              // Locked rotor toreque
+nr=ns*(1-s);
+
+// (c) In rush line current line current when starting at reduced voltage
+a=1/0.65;                         // Bank ratio of autotransformer
+IHS=ILS/a;
+
+// Display result on command window
+printf("\n Locked rotor torque = %0.1f lb-ft ",Tlr);
+printf("\n Expected average in-rush current = %0.0f A ",Ilr);
+printf("\n Locked rotor torque when motor is started at reduced voltage = %0.1f lb-ft ",T2);
+printf("\n In-rush line current = %0.0f A",IHS);
+
+