In d.c. machine iron losses occur in
WebFeb 24, 2012 · These losses occur due to current flowing in stator and rotor windings. As the load changes, the current flowing in rotor and stator winding also changes and hence these losses also changes. Therefore these losses are called variable losses. The copper losses are obtained by performing blocked rotor test on three phase induction motor. WebThe condition for maximum efficiency for a D.C. generator is. A. Eddy current losses = stray losses. B. Hysteresis losses = eddy current losses. C. Copper losses = 0. D. Variable losses = constant losses. View Answer.
In d.c. machine iron losses occur in
Did you know?
WebAug 22, 2024 · Different losses which occur in a dc motor can be roughly divided into following three classes. Copper losses, Iron losses or Core losses, Mechanical losses; … WebMar 8, 2024 · In a DC generator, the iron losses mainly take place in ________ Yoke Commutator Armature conductors Armature rotor Show Explanation 6. A DC generator delivers a 30-A current to a load at 120 V by consuming 4500 J/s of mechanical energy. Determine the efficiency of the generator. 90% 85% 75% Show Explanation 7.
WebQuestion: 8) 8) Iron losses occur in the armature of a DC machine. A) True B) False 9) 9) A DC motor running at no load develops no useful power. A) True B) False 10) 10) At no … WebJul 5, 2024 · 7.Hysteresis losses in a dc generator are basically due to (a) Current flowing in the armature core (b) reversal of magnetism of the armature core (c) initial energy to magnetise the core (d) none of these Ans: b 8.A d.c. shunt motor runs at 500 r.p.m. at 220 V. A resistance of 4.5 Ω is added in series with the armature for speed control.
WebIn a dc machine mechanical losses occur due to (a) air resistance of rotation to armature and fan. (b) brush friction. (c) bearing friction. (d) all of the above. SHOW ANSWER 17. In a dc machine, mechanical losses are primarily function of (a) voltage. (b) current. (c) speed. (d) none of these. SHOW ANSWER 18. WebMar 16, 2024 · The losses occur in the machine mainly are: Iron losses in the core Friction and windings losses Armature copper loss. Since the no load mechanical output of the machine is zero in Swinburne's test, the no load input power is …
Web(a) List any four (4) types of losses that occur in DC machines. (4 marks) (b) A 240 V, 1500 rpm DC shunt motor draws a current of 65 A during half load operation. The rotational losses are 1500 W at rated power output. The armature circuit resistances are given as 0.05Ω and 120Ω, respectively.(i) Calculate the efficiency and torque of the motor under …
WebJan 21, 2024 · Copper loss is those which occur in the windings of the dc machine. Generally, there are field and armature windings in a dc machine, and losses are named … csusb health portalWebAug 18, 2024 · Digital Electronics Electron Electronics & Electrical. The power losses which occur in a transformer are of two types −. Core or Iron Losses ( Pi) Copper Losses or I 2 R Losses ( Pcu) The losses in a transformer appears in the form of heat which increases the temperature and reduces the efficiency. csusb health and wellness centerWebOct 31, 2024 · Basically, determining of these losses is somewhat complicated. So, it is required to allocate the acceptable value of stray losses. In many of the d.c machines, stray losses are considered as a convention to be 1% of the whole load resultant power. Both the mechanical and the iron losses are collectively termed as stray losses. csusb health condomsearly withdrawal tax penaltyWebOct 18, 2024 · What are the components of iron loss in a dc machine and in which part of the machine it occurs? Answer. Iron loss consists of hysteresis and eddy current losses caused by changing flux densities in the iron core. Hysteresis loss incurs in revolving armature and teeth of a dc machine. early withdraw roth iraWebThe losses in the DC machine are as follows: #1. Electrical or Copper Losses in DC Machine: Electrical or copper losses occur in stator windings and armature windings in DC … early wobbly collectionWebAug 1, 2024 · Iron loss is one of the major losses in electrical machines. The accurate prediction of the iron loss is essential for the electromagnetic and thermal design of … csusb health office