# Lifting_electromagnet

Document Sample

```					Lifting_electromagnet.xls
To determine magnet properties to lift a mass, remember, like current in a
series circuit, the flux in a series magnetic circuit is constant.
Enters numbers in BOLD, Results in RED
Mass of object to lift, M (kg)                                              0.5
Force required to lift object, F (N)                                        4.9
Total required Magnetomotive force, MMFtotal (At)                          37.6
Available current, Iavail (amps)                                          0.5
Minimum number of required turns                                         75.2
Air gap
Area of first pole, Ap_1 (mm^2)                                           600                                         1.8
Length of first air gap, Lag1 (mm)                                        0.1                                         1.7
Area of second pole, Ap_2 (mm^2)                                          600
Length of second air gap, Lag2 (mm)                                       0.1                                         1.6
Required magnetic flux density to lift object, Breq (Tesla)            0.101                                          1.5

Magnetic flux density B (T = tesla)
Magnetic field intensity Fm @Breq, MMFag (At)                            16.1
Required magnetic circuit flux, phi (Wb)                            6.08E-05                                            1.4
Lifting magnet                                                     sheet steel                                          1.3
Section 1
Magnetic circuit path length, L_1 (mm)                                  25                                         1.2
Magnetic circuit path area, A_1 (mm^2)                                 600                                         1.1
Flux density, B_1 (Tesla)                                           0.101
From B-H curve, magnetic field intensity, H_1 (At/m)                    50                                         1.0
Magnetomotive force (MMF), MMF_1 (At)                                 1.25
Section 2
0.9
Magnetic circuit path length, L_2 (mm)                                  60                                         0.8
Magnetic circuit path area, A_2 (mm^2)                                 600
Flux density, B_2 (Tesla)                                           0.101
0.7
From B-H curve, magnetic field intensity, H_2 (At/m)                    50                                         0.6
Magnetomotive force (MMF), MMF_2 (At)                                    3
Section 3
0.5
Magnetic circuit path length, L_3 (mm)                                  25                                         0.4
Magnetic circuit path area, A_3 (mm^2)                                 600
Flux density, B_3 (Tesla)                                           0.101
0.3
From B-H curve, magnetic field intensity, H_3 (At/m)                    50                                         0.2
Magnetomotive force (MMF), MMF_3 (At)                                 1.25
Object being lifted                                                  cast iron
0.1
Magnetic circuit path length, Lobl (mm)                                    80                                         0.0
Magnetic circuit path area, Aobl (mm^2)                                  600
0   400   800   1200   1600
Flux density, Bobl (Tesla)                                            0.101
From B-H curve, magnetic field intensity @Breq, Hobl (At/m)               200
Magnetomotive force (MMF), MMFobl (At)                                     16
Magnetic f
Permeativity of free space, mu0 (H/m)                               1.26E-06

4.7279E-05
Magnetomotoive force (MMF) (number of Ampere-turns) is required to force the needed flux
through the reluctances in the magnetic circuit:

1.8
1.7
1.6
1.5
Magnetic flux density B (T = tesla)

1.4
1.3
1.2                                                                    Mild steel
1.1                                                                    Cast steel
1.0                                                                    Cast iron
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0   400   800   1200   1600   2000   2400   2800   3200   3600   4000   440

Magnetic field intensity H (At/m = ampere-turn
Mild steel sheet
Cast steel
Cast iron

0   3600    4000   4400   4800   5200   5600   6000

m = ampere-turns/meter)

```
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
 views: 12 posted: 11/28/2011 language: English pages: 3