Electrical Machines What is power factor of a 3 - φ induction motor at no load? Low. Equal to 1. Same as full load. High. Low. Equal to 1. Same as full load. High. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature resistance of a permanent magnet dc motor is 0.8 Ohm. At no load, the motor draws 1.5 A from a supply voltage of 25 V and runs at 1500 rpm. The efficiency of the motor while it is operating on load at 1500 rpm drawing a current of 3.5 A from the same source will be 48.0%. 57.1%. 59.2%. 88.8%. 48.0%. 57.1%. 59.2%. 88.8%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The damper windings also called the squirrel cage windings or damper grids consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing equalizer rings. carbon brushes. commutator with large number of segments. graphite brushes. equalizer rings. carbon brushes. commutator with large number of segments. graphite brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the reason for stationary armature essential in alternators above 5 KVA? Operating cost is less. Insulation requirement is less. Collecting of large current is simple. All of these Operating cost is less. Insulation requirement is less. Collecting of large current is simple. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM in order to eliminate cogging the number of stator slots must be equal to number of rotor slots. an integral multiple of number of rotor slots. unequal to number of rotor slots and skewed in shape. either (B) or (C). equal to number of rotor slots. an integral multiple of number of rotor slots. unequal to number of rotor slots and skewed in shape. either (B) or (C). ANSWER DOWNLOAD EXAMIANS APP