Documenting the intended service conditions is a strategic imperative for compliance. Clause 3 of IEC 183 mandates a comprehensive analysis of the electrical and environmental stresses the cable system will endure throughout its operational life. This information directly dictates the required cable specifications, and its formal documentation is a key audit point. The compliance audit must verify the definition and documentation of the following parameters:

• Nominal system voltage
• Highest voltage of the three-phase system (Um)
• Lightning overvoltage characteristics (Up)
• System frequency
• Type of system earthing, including the maximum permitted duration of earth fault conditions for any single occasion and the total duration per year.
• Environmental conditions, specifying if the altitude exceeds 1000 m, whether the installation is indoor or outdoor, and if excessive atmospheric pollution is expected.
• Design clearance and insulation for all connecting equipment, such as transformers and switchgear.
• Maximum rated current, with the operational mode clearly detailed as one of the following: (1) continuous, (2) cyclic, or (3) emergency/overload. The standard notes that a load curve is essential for determining conductor size in cyclic operations.
• Symmetrical and asymmetrical short-circuit currents that are expected to flow in case of a fault, both between phases and to earth.
• Maximum duration for which these short-circuit currents may flow.

Once these operating and environmental conditions are formally documented and verified, the next logical step in the audit is to confirm the physical installation parameters.