Electrical Machines In DC motors, under trailing pole tips, flux density will_______ ? increase None of these decrease either increase or decrease increase None of these decrease either increase or decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous reactance( Xs) is the combined reactance due to armature reaction and leakage flux reactance due to armature reaction of the machine reactance due to leakage flux reactance either due to armature reaction or leakage flux combined reactance due to armature reaction and leakage flux reactance due to armature reaction of the machine reactance due to leakage flux reactance either due to armature reaction or leakage flux ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward-Leonard system for controlling the speed of a DC motor is used where All of above. The speed in both the direction is required. The accuracy in speed control is required. Very fine speed control over the whole range from zero to normal speed is required. All of above. The speed in both the direction is required. The accuracy in speed control is required. Very fine speed control over the whole range from zero to normal speed is required. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine shape of armature MMF wave is? Triangular and directed towards brush axis. Saddle shape. Triangular and directed towards main pole. Peaky in nature. Triangular and directed towards brush axis. Saddle shape. Triangular and directed towards main pole. Peaky in nature. ANSWER DOWNLOAD EXAMIANS APP