Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a DC motor at the time of starting is Normal. Very low. Very high. Zero. Normal. Very low. Very high. Zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator, lap winding is used in high current and low voltage applications. high voltage and low current applications. where constant speed is required. where greater load is connected. high current and low voltage applications. high voltage and low current applications. where constant speed is required. where greater load is connected. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V-curve of synchronous motor shows the variation of supply voltage and field current at constant excitation power factor and supply voltage during hunting power factor and dc excitation at constant load All of these supply voltage and field current at constant excitation power factor and supply voltage during hunting power factor and dc excitation at constant load All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Pi and Pc represent core and full load copper loss respectively, the maximum KVA delivered to load corresponding to maximum efficiency is equal to rated KVA is Pi/Pc (Pi/Pc)2 Pc/Pi √(Pi/Pc) Pi/Pc (Pi/Pc)2 Pc/Pi √(Pi/Pc) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor drawing an armature current of Ia is operating under saturated magnetic conditions. The torque developed in the motor is proportional to Ia Ia2 1/Ia I/Ia2 Ia Ia2 1/Ia I/Ia2 ANSWER DOWNLOAD EXAMIANS APP