Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 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. 2 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC generator will not build up voltage any one of above. due to wrong direction of rotation. if it has lost residual magnetism. if field resistance is more than critical resistance. any one of above. due to wrong direction of rotation. if it has lost residual magnetism. if field resistance is more than critical resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is rectangular flat-topped co- sinusoidal sinusoidal rectangular flat-topped co- sinusoidal sinusoidal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the brushes remain in contact with conductors which lie under north pole. there is no hard and fast rule for this. lie in the inter polar gaps. lie under south pole. lie under north pole. there is no hard and fast rule for this. lie in the inter polar gaps. lie under south pole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field circuit of a DC shunt motor is opened DC Shunt Motor The speed of motor will be reduced. The motor will attain dangerously high speed. The armature current will reduce. DC Shunt Motor The speed of motor will be reduced. The motor will attain dangerously high speed. The armature current will reduce. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 38.5 Nm. 74 Nm. 65.8 Nm. 27.73 Nm . 38.5 Nm. 74 Nm. 65.8 Nm. 27.73 Nm . ANSWER DOWNLOAD EXAMIANS APP