(b) Figure Q3(b) shows a magnetic circuit with two different material, with a mean cross- sectional area of 25 cm2. The mean core length of steel, Lsı and Ls2 is 20 cm and 15 cm, respectively. The mean core length of iron, LI1 and Ln is 20 cm and 14 cm, respectively. The air gap length, Lag is 1 cm. Relative permeability of steel and iron is 7000 and 4000 respectively. Fringing effect is excluded. Calculate; Steel Iron Ls1 N2 Lag Steel N1 Iron L11 Ls2 It Figure Q3(b) (i) Total reluctances of this magnetic circuit. (ii) Total magnetomotive force required to produced 60 µWb of flux across the air- gap. (iii) Number of turns in coil 1, N1 if both electrical source supply the same amount of current, 5A, assume N1 = N2.

(b) Figure Q3(b) shows a magnetic circuit with two different material, with a mean cross- sectional area of 25 cm2. The mean core length of steel, Lsı and Ls2 is 20 cm and 15 cm, respectively. The mean core length of iron, LI1 and Ln is 20 cm and 14 cm, respectively. The air gap length, Lag is 1 cm. Relative permeability of steel and iron is 7000 and 4000 respectively. Fringing effect is excluded. Calculate; Steel Iron Ls1 N2 Lag Steel N1 Iron L11 Ls2 It Figure Q3(b) (i) Total reluctances of this magnetic circuit. (ii) Total magnetomotive force required to produced 60 µWb of flux across the air- gap. (iii) Number of turns in coil 1, N1 if both electrical source supply the same amount of current, 5A, assume N1 = N2.

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter12: Electronic Control Devices

Section: Chapter Questions

Problem 14RQ

See similar textbooks

Similar questions

An air gap has a length of 0.1 cm. What length of iron core has the same reluctance as the air gap? The relative permeability of the iron is 5000. Assume that the cross-sectional areas of the gap and the core are the same.
Which of the following is not true for ferromagnetic materials? Please choose one: a. High?mthey have value. b.Above the Curie temperature, they lose their non-linear properties. C. a fixedµrthey have value. D.The energy loss is proportional to the area of the hysteresis loop.
(b) Figure Q3(b) shows a magnetic circuit with two different material. with a mean cross- sectional area of 25 cm?. The mean core length of steel, Ls1 and Ls2 is 20 cm and 15 cm, respectively. The mean core length of iron, Li1 and Lp is 20 cm and 14 cm, respectively. The air gap length, Lag is 1 cm. Relative permeability of steel and iron is 7000 and 4000 respectively. Fringing effect is excluded. Calculate; Steel Iron Ls1. I2 N2 Steel N1 Iron L11 Ls2. Figure Q3(b) (i) Total reluctances of this magnetic circuit. (ii) Total magnetomotive force required to produced 60 µWb of flux across the air- gap. (iii) Number of turns in coil 1, N1 if both electrical source supply the same amount of current, 5A, assume N1 = N2.
Consider a ferromagnetic ring (nucleus) that has a mean circumference of 40 cm, 300coiled copper turns and a sectional area of 5 cm2. A current of 2 is appliedA to winding, producing a flux of 1.5 mWb.Determine the permeability of the core material.Determine the relative permeability of the core material.If the ferromagnetic ring has an air gap of 2 mm. Find the required MMFso that the flux density in the gap is 0.5 T.
1.2 Magnetic Circuits The figure shows a ferromagnetic core whose mean path length is 40cm. There is a small gap of 0.05 cm in the structure of the otherwise whole core. The cross-sectional area of the core is 12 cm², the relative permeability of the core is 4000, and the coil of wire on the core has 400 turns. Assume that fringing in the air gap increases the effective cross-sectional area of the air gap by 5 percent. Mr = 4000 N=400 turns ·25.4m² Il=0.0005m A=0.0012 m² Given this information: a) Find the total reluctance of the flux path (iron plus air gap). b) Find the current required to produce a flux density of 0.5 T in the air gap. c) Qualitatively describe the effect of the air gap on the magnetic circuit.
The saturation curve of a particular core material shows that at a magnetic field intensity of 1250 At/m and the flux density is 0.80 Tesla. Determine the relative permeability of the core material.
An iron core has a cross-sectional area of 10-3 square meter and mean circumference of 1 meter. The relative permeability of the material is 500 and the number of turns is 200. Determine the current required to set up a flux of 0.001 weber.
Explain the following. A. Magnetic Field Strength B. Boundary Conditions
25 PROBLEMS 12 cm +1.5-mm gap IP1000t Armature (sheet steel) Cast steel A = 2 cm? throughout FIGURE 1.27. The relay shown in Figure 1.27 has a core made of cast steel and an armature of sheet steel. A flux of 0.8 T in the air gap produces a force that pulls in the CO armature. a. Determine the required current to pull in the armature. b. What force is exerted on the armature to overcome the spring tension? c. Assuming in the closed position the air gap is reduced to 0.1 mm, to what value may the current be reduced (dropout current of relay) just to retain closure? Assume that the same force is required in the closed position to overcome the spring force.
The applied MMF to a simple magnetic circuit is 350AT. It was found that the resulting magnetic field denstiy is 0.7 Wb/m². The average length of this magnetic circuit is 1.64ft and its cross sectional area is 4cm². What is the reluctance (in AT/Wb) of the magnetic material of the core?
An air-gap between two pole pieces is 20 mm in length and the area of the flux path across the gap is 5 cm². If the flux required in the air-gap is 0.75 mWb find the m.m.f. necessary.
A mmf is supplied by a current of 1 A through 100 turns. The magnetic unit consists of a steel core of 800 relative permeability, length of 10 cm and cross-sectional area of 4 cm2 and an air gap of 1 cm long. What is the total reluctance of the magnetic circuit in AT/Wb?