A class 2 copper rope refers to the specific parameters of the wire. Electrical cables are classified according to their flexibility, meaning not only their ability to bend more easily but also other aspects linked to the structure of the cable itself.
The flexibility depends on the diameter of the individual wires present in the cable. This parameter is so important that it is regulated in the table of IEC 60228, the International Electrotechnical Commission’s international standard on conductors of insulated cables.
Based on the different applications and properties of the wires, it is possible to choose cables of different classes, taking into account the information expressed in the table.
Flexibility classes for electrical cables
There are four classes of flexibility for electrical cables:
- Class 1: ideal conductors for permanent installations;
- Class 2: conductors designed for fixed installation;
- Class 5: flexible conductors, preferred in cases of vibration, bending or reduced range of movement;
- Class 6: very flexible conductors.
Nevertheless, the IEC 60228 table also takes into account two other important parameters: size and resistance. In terms of size, it assesses the nominal cross-section area for standard conductors; for example, for class 1 and class 2 cables , it takes into consideration the minimum number of strands required to create specific sizes of the conductor, while for classes 5 and 6 , it takes into account the maximum diameter of any part of the conductor.
The resistance, on the other hand, is measured in ohm/km and takes into account the maximum permissible for each size, class and type of conductor. The aim of this classification is to provide a standard definition of the various conductors, as copper can have different resistance values even with the same dimensions. Whereas by taking into account the nominal size determined by the resistance, the parameters can be standardised and the comparison is more significant.
Class 2 copper rope
A class 2 copper rope has very precise technical characteristics: you can simply take a look at the IEC 60228 table to see the main differences compared to other conductors.
For example, while class 1 cables can contain a single wire, a class 2 copper rope consists of at least 7 individual wires with a smaller diameter than the previous class. Despite the clear average difference in diameter, a class 2 cable is not very flexible so it is not recommended for applications involving bends or a reduced range of movement.
However, class 2 conductors are more resistant in corrosive atmospheric conditions and high temperatures, or when welding is required. They must always be covered by a sleeve, which provides better protection not only in terms of electrical insulation but also from a mechanical point of view.