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Differences between revisions 14 and 15
⇤ ← Revision 14 as of 2018-07-17 07:09:40 →
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Editor: KeithLofstrom
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← Revision 15 as of 2018-07-17 07:37:20 → ⇥
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[[ attachment:skindepth.ods | !LibreOffice Spreadsheet]]

Skin Depth

=2r0  in m ~=~ \sqrt{ 2.533e11 \rho / f \mu_r } ~~ in mm ~~~~~~ 2 / 2 \pi \mu_0 = 253303 m/H

Material

Temp

perm.

resis.

depth (mm) at frequency

K

\mu_r

\rho~~\Omega-m

1 Hz

60 Hz

400 Hz

1 KHz

5 KHz

20 KHz

200 KHz

3% Si Transformer Steel

300

700

5e-7

13.4

1.7

0.67

0.43

0.19

0.95

0.030

3% Si Transformer Steel

600

300?

7e-7?

24.3

3.1

1.2

0.77

0.34

0.17

0.054

Copper

300

1

1.7e-8

65.6

8.5

3.3

2.1

0.93

0.46

0.15

Copper

600

1

3.8e-8

98.1

13

4.9

3.1

1.4

0.69

0.22

Aluminum

300

1

2.8e-8

84.2

11

4.2

2.7

1.2

0.60

0.19

Aluminum

600

1

5.9e-8

122.2

16

6.1

3.9

1.7

0.86

0.27

Resistivity - for copper see Matula 1979 page 1161, for aluminum see Simmons 1960

!LibreOffice Spreadsheet

SkinDepth (last edited 2018-07-18 17:58:39 by KeithLofstrom)