Understanding of wires and cables flexibility.
- What’s a wire flexibility class?
Electric conductor – the main element of a cable or wire structure. Electric current passes exactly through the electric conductor , transmitting electrical energy from a source to a consumer.
Electric conductor comes in two basic varieties: solid and stranded wire.
Stranded wire is more flexible than solid wire of the same total cross-sectional area.
- How to define the class of wire flexibility?
Based on the flexibility, depending on how many wires are in the core, there is a classification of wires into 6 classes of flexibility. As the wire class increases, the flexibility of a cable product based on it increases respectively. The higher the flexibility class, the more flexible cable products.
According to the standard there are 6 classes of electric conductor flexibility:
Wire flexibility class |
Wire cross-section (mm2) |
2,5 |
4 |
6 |
10 |
16 |
25 |
35 |
50 |
70 |
95 |
120 |
150 |
185 |
240 |
||
Class 1 |
Copper/ aluminum wire |
(mm) |
1,8 |
2,3 |
2,8 |
3,6 |
4,5 |
5,7 |
6,6 |
8 |
9,42 |
11 |
12,3 |
13,7 |
15,2 |
17,3 |
|
Number of cords in a wire |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 (35) |
1 (35) |
|||
Class 2 |
Copper/ aluminum wire |
Nominal diameter (mm) |
2 |
2,6 |
3,1 |
4,1 |
5,1 |
6,4 |
7,56 |
8,9 |
10,7 |
12,6 |
14,2 |
15,8 |
17,64 |
20,25 |
|
Number of cords in a wire |
7 |
7 |
7 |
7 |
7 |
6 |
6 |
6 |
12 |
15 |
18 |
18 |
30 |
30 |
|||
Class 3 |
Copper wire |
Nominal diameter (mm) |
2,1 |
2,6 |
3,2 |
4 |
5,2 |
6,8 |
7,65 |
9,41 |
10,7 |
12,5 |
14,4 |
16 |
17,6 |
- |
|
Number of cords in a wire |
7 |
7 |
19 |
19 |
19 |
19 |
19 |
27 |
37 |
37 |
61 |
61 |
91 |
- |
|||
Class 4 |
Copper wire |
Nominal diameter (mm) |
212 |
2,7 |
3,2 |
4,5 |
5,8 |
7,2 |
8,89 |
11,5 |
10,2 |
14,8 |
17 |
18,7 |
22,61 |
24,03 |
|
Number of cords in a wire |
20 |
20 |
30 |
49 |
49 |
49 |
98 |
144 |
189 |
189 |
266 |
266 |
330 |
420 |
|||
Class 5 |
Copper wire |
Nominal diameter (mm) |
2,1 |
3 |
3,7 |
5,3 |
6 |
7,8 |
9,04 |
10,8 |
12,8 |
14,5 |
16,8 |
19,7 |
21,53 |
23,45 |
|
Number of cords in a wire |
50 |
56 |
84 |
80 |
224 |
196 |
189 |
266 |
266 |
361 |
608 |
756 |
925 |
1221 |
|||
Class 6 |
Copper wire |
Nominal diameter (mm) |
2,4 |
3,1 |
3,7 |
5,1 |
6,2 |
788 |
9,84 |
11,4 |
12,9 |
14,7 |
17,1 |
18,9 |
20,37 |
23,72 |
|
Number of cords in a wire |
140 |
228 |
189 |
324 |
513 |
783 |
1107 |
402 |
999 |
1332 |
1702 |
2109 |
2590 |
3360 |
Visual demonstration of the flexibility classification:
Wires of classes 1 and 2 are intended for cable products of fixed installation. Wires of classes 3, 4, 5 and 6 are designed for flexible cable products, but they can also be used for cable products of fixed installation.