Electrical Machines In which of the following, voltage regulation may be zero or negative All of these unity power factor lagging power factor leading power factor All of these unity power factor lagging power factor leading power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1, 2, and 3 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 1 and 3 2, 3 and 4 1, 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A cumulatively compounded dc motor delivers rated load power at rated speed. If the series field is short-circuited, then both armature current Ia and speed ωm increase Ia increases and ωm decreses both decrese Ia remains constant but ωm increase both armature current Ia and speed ωm increase Ia increases and ωm decreses both decrese Ia remains constant but ωm increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low resistivity. low viscosity. low BDV. high viscosity. low resistivity. low viscosity. low BDV. high viscosity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a dc machine shunt resistance and armature resistance values are high and high high and low low and low low and high high and high high and low low and low low and high ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a cumulatively compound DC motor can be controlled by varying Armature resistance control. Shunt field resistance control. Armature voltage control. Any of above. Armature resistance control. Shunt field resistance control. Armature voltage control. Any of above. ANSWER DOWNLOAD EXAMIANS APP