Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 2 at 90°C. 1 at 90°C. 3 at 90°C. 0.5 at 90°C. 2 at 90°C. 1 at 90°C. 3 at 90°C. 0.5 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately excited DC motor has an armature resistance of 0.5 Ohm. The supply voltage is 250V. Armature current is 20A and the speed of rotation is 1500 rpm. Find the torque developed? 15.6 Nm 15.28 Nm Zero 16.55 Nm 15.6 Nm 15.28 Nm Zero 16.55 Nm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward Leonard control is provides speed control Above rated speed. In both direction. In one direction only. Below rated speed. Above rated speed. In both direction. In one direction only. Below rated speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following pairs is/are correct? closed slot----- leakage flux is high open slot----- leakage flux is less semi closed slot-----leakage flux is moderate All of these closed slot----- leakage flux is high open slot----- leakage flux is less semi closed slot-----leakage flux is moderate All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 0.75 Hz. 0.70 Hz. 0.65 Hz. 60 Hz. 0.75 Hz. 0.70 Hz. 0.65 Hz. 60 Hz. ANSWER DOWNLOAD EXAMIANS APP