Electrical Machines The low voltage winding of a 400/230 V single phase 50 Hz transformer is to be connected to keep the magnetization current at the same level in both the cases the voltage at 25 Hz should be 65 V 230 V 115 V 460 V 65 V 230 V 115 V 460 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by increasing the excitation. cooling the armature. increasing the input to the prime mover. reducing the load voltage. increasing the excitation. cooling the armature. increasing the input to the prime mover. reducing the load voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is power factor of a 3 - φ induction motor at no load? Same as full load. Low. High. Equal to 1. Same as full load. Low. High. Equal to 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 4575.4 r.p.m. 963.8 r.p.m. 1037.5 r.p.m. 1130 r.p.m. 4575.4 r.p.m. 963.8 r.p.m. 1037.5 r.p.m. 1130 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Secondary winding of an auto transformer is also called common winding. compensating winding. damping winding. tertiary winding. common winding. compensating winding. damping winding. tertiary winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 10.8Ω and Xq = 8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9Ω and Xq = 9.6Ω ANSWER DOWNLOAD EXAMIANS APP