Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. None of these. Both of above. Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. None of these. Both of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V curve of synchronous motor shows variation of power factor and supply voltage during hunting. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. power factor and supply voltage during hunting. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous generator, inverted V curve is drawn between field current on X-axis and power factor on Y-axis field current on X-axis and armature current on Y-axis field current on Y-axis and power factor on X-axis field current on Y-axis and armature current on X-axis field current on X-axis and power factor on Y-axis field current on X-axis and armature current on Y-axis field current on Y-axis and power factor on X-axis field current on Y-axis and armature current on X-axis ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC Series motor, speed lower than the rated speed can be obtained by Any of the above. Connecting an additional resistance in stator circuit. Connecting an additional resistance in the field circuit. Connecting an additional resistance in the armature circuit. Any of the above. Connecting an additional resistance in stator circuit. Connecting an additional resistance in the field circuit. Connecting an additional resistance in the armature circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Number of secondary turns is less than primary turns. Secondary power is less than primary power. Secondary current is less than primary current. Number of secondary turns is more than that of primary. Number of secondary turns is less than primary turns. Secondary power is less than primary power. Secondary current is less than primary current. Number of secondary turns is more than that of primary. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a DC motor can be determent by Flemings left hand rule. Amperes law. Flemings right hand rule. Lenzs law. Flemings left hand rule. Amperes law. Flemings right hand rule. Lenzs law. ANSWER DOWNLOAD EXAMIANS APP