The cables listed in this Standard are designated by the rated voltages Uo and U expressed in the form Uo/U where

Uo is the power-frequency voltage to earth for which the cable is designed

U is the power-frequency voltage between conductors for which the cable is designed.

The electric power and lighting cables listed in the standard range are suitable for operation in the following conditions:

Where the combination of ambient temperature and temperature rise due to load results in a conductor temperature not exceeding:

70°C for the items in Table 1 and Table 2

60°C for the item in Table 3.

Where, in the case of a short circuit, the maximum conductor temperature does not exceed:

160°C for the items in Table 1 and Table 2

200°C for the item in Table 3.

Current ratings have not been shown in the Tables because of the wide range of conditions in which the cables may be used. Current ratings according to the conditions of use may be obtained from the IEE 'Regulations for the electrical equipment of buildings'.

Following the changes to the IEE 'Regulations for the electrical equipment of buildings' the core colours of these power cables have been amended to reflex these changes.