Wire Conventions

Wire Conventions

 

 

Color conventions

 

In many cases, the color of a wire's insulation determines it's function. The specifics tend to differ from country to country, though many things stay consistent, such as the color of ground wires. 

The table below shows the colors for AC power in Canada. [2]

Function

Label

Color

Function

Label

Color

Protective Ground

PG

Green/green-yellow

Neutral

N

White

Line, single phase

L

Black or Red

Line 1

L1

Red

Line 2

L2

Black

Line 3

L3

Blue

A green-yellow ground wire [1]

A green-yellow ground wire [1]

A green-yellow ground wire connected to a grey metal pipe running vertically outside a brick wall
Ground wire

 

Wire Gauge

 

Wire gauge refers to the diameter of a wire. A wider gauge leads to a higher current capacity, also referred to as ampacity, which allows it to carry more current before overheating [4]. For alternating current, the effects of skin effect also increase as the gauge increases in size, which leads to greater attenuation of the signal [5]. There are multiple standards for wire gauge used. In Canada, you will run into American wire gauge, sometimes referred to as Browne and Sharpe gauge and abbreviated as AWG. In AWG, increase in gauge number represents a decrease of around 12% of the wire's diameter and around 26% in it's area. The largest gauge is 0000, followed by 000, 00 and 0. These are sometimes denoted 4/0, 3/0 2/0 and 1/0 respectively. From there on it counts up from 1 to 40, 40 being the smallest. All sizes are measured in inches. There also exist the Standard wire gauge, Circular Mil area and Birmingham wire gauge. Standard wire gauge is used in Britain and is similar to American wire gauge. The largest size is 7/0, which counts down to 1/0. From there on out, it goes from 1 to 50, 50 being the smallest size. [6]

 

Below is a table with some of the values for AWG [6]

American wire gauge

Diameter (inches)

Diameter (millimeters)

Area (mm2)

Ampacity for copper wire (A)

Max Frequency for 100% skin depth on copper wire (Hz)

American wire gauge

Diameter (inches)

Diameter (millimeters)

Area (mm2)

Ampacity for copper wire (A)

Max Frequency for 100% skin depth on copper wire (Hz)

0000 or 4/0

0.46

11.684

107

302

125

000 or 3/0

0.4096

10.40384

85

239

160

00 or 2/0

0.3648

9.26592

67.4

190

200

0 or 1/0

0.3249

8.25246

53.5

150

250

1

0.2893

7.34822

42.4

119

325

2

0.2576

6.54304

33.6

94

410

3

0.2294

5.82676

26.7

75

500

4

0.2043

5.18922

21.2

60

650

5

0.1819

4.62026

16.8

47

810

6

0.1620

4.1148

13.3

37

1100

7

0.1443

3.66522

10.5

30

1300

8

0.1285

3.2639

8.37

24

1650

9

0.1144

2.90576

6.63

19

2050

10

0.1019

2.58826

5.26

15

2600

15

0.0571

1.45034

1.65

4.7

8250

20

0.0320

0.8128

0.518

1.5

27000

25

0.0179

0.45466

0.162

0.457

85000

30

0.010

0.254

0.0509

0.142

270000

35

0.0056

0.14224

0.016

0.044

870000

40

0.0031

0.07874

0.00501

0.0137

2900000

American wire gauge [3]

American wire gauge [3]

A tool used to measure American wire gauge, pictured against a plain white background
American wire gauge

 

 

References

[1]

A. K, Home Earth Australia Rod. Wikimedia, 2006.

[2]

“Wiring color codes,” All About Circuits. [Online]. Available: https://www.allaboutcircuits.com/textbook/reference/chpt-2/wiring-color-codes/. [Accessed: 19-Oct-2021].

[3]

WIRE GAUGE AMERCAIN STD 0-36. Grainger.

[4]

R. Regole, “What is wire ampacity and why its calculation is critical,” Iconn Systems, 29-Aug-2016. [Online]. Available: https://www.iconnsystems.com/blog/ampacity. [Accessed: 16-Nov-2021].

[5]

R. Hranac, “Skin effect and skin depth,” Broadband Library, 22-May-2020. [Online]. Available: https://broadbandlibrary.com/skin-effect-and-skin-depth/. [Accessed: 16-Nov-2021].

[6]

“American wire gauge conductor size table” Solaris shop. [Online]. Available: https://www.solaris-shop.com/content/American%20Wire%20Gauge%20Conductor%20Size%20Table.pdf. [Accessed: 24-Oct-2021].

 

 

 

 

Contributions: 

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Mayurakhi Khan (Deactivated) 1664 days ago

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