Conductor Formation

Nominal
Cross
Sectional
Areas

CIRCULAR
CONDUCTORS

No. & Nominal
Diameters
of Wires

SHAPED OR CIRCULAR
COMPACTED
CONDUCTORS

Minimum Number
or Wires 

MAXIMUM
RESISTANCE
AT 20OC
ohm / km

FLEXIBLE
CONDUCTORS

mm2

mm

        Cu

 Al

      Cu  

Al

   (mm)Cu  

ohm / km

1 (s)
1.5 (s)
2.5 (s)

4
6
10

16
25
35

50
70
95

120
150
185

240
300
400

500
630
800

1000

1/1.13
1/1.38
1/1.77

7/0.85
7/1.04
7/1.35

7/1.70
7/2.14
7/2.52

19/1.78
19/2.14
19/2.52

37/2.03
37/2.25
37/2.52

61/2.25
61/2.52
61/2.85

61/3.20
127/2.52
127/2.85

127/3.20

-
-
-
-
-
-

6
6
6

6
12
15

18
18
30

34
34
53

53
53
-

-

-
-
-
-
-
-

6
6
6

6
12
15

15
15
30

30
30
53

53
53
-

-

18.1
12.1
7.41

4.61
3.08
1.83

1.15
0.727
0.524

0.387
0.268
0.193

0.153
0.124
0.0991

0.0754
0.0601
0.0470

0.0366
0.0268
0.0221

0.0176

-
-
-

7.41
4.61
3.08

1.91
1.20
0.868

0.641
0.443
0.320

0.253
0.206
0.164

0.125
0.100
0.0778

0.0605
0.0469
0.0367

0.0291

0.21
0.26
0.26

0.31
0.31
0.41

0.41
0.41
0.41

0.41
0.51
0.51

0.51
0.51
0.51

0.51
0.51
0.51

0.61
0.61
-

-

19.5
13.3
7.98

4.95
3.30
1.91

1.21
0.780
0.554

0.386
0.272
0.206

0.161
0.129
0.106

0.0801
0.0641
-

-
-
-

-