Electrical Machines Find the number of poles required, when the frequency is 50Hz and speed of the motor is 500 rpm? 12 5 10 24 12 5 10 24 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole lap wound dc generator has 4 brushes, if one of the brush is damaged, what will be the change in V, I and P ratings V/2, I and P/2 V, I and P V/2, I/2 and P/4 V, I/2 and P/2 V/2, I and P/2 V, I and P V/2, I/2 and P/4 V, I/2 and P/2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to withstand twisting strains due to transmission of torque. any unbalanced magnetic pull on the armature core. bending moment due to weight of the armature. All of these twisting strains due to transmission of torque. any unbalanced magnetic pull on the armature core. bending moment due to weight of the armature. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The full load copper loss and iron loss of transformer are 6400W and 5000W respectively. The copper loss and iron loss at half load will be respectively? 1600 W and 5000 W 3200 W and 2500 W 3200 W and 5200 W 1600 W and 1250 W 1600 W and 5000 W 3200 W and 2500 W 3200 W and 5200 W 1600 W and 1250 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines No load saturation characteristics are plotted between short circuit current and field current short circuit current and armature current no load voltage and armature current no load voltage and field current short circuit current and field current short circuit current and armature current no load voltage and armature current no load voltage and field current ANSWER DOWNLOAD EXAMIANS APP