How to Choose Power Cable for an Industrial Project

Define the Electrical Duty

Record rated voltage, phase, frequency, continuous current, starting current and the type of load. Motors, transformers, variable-frequency drives and ordinary distribution feeders can place different thermal and electrical stresses on cable.

Choose a cable voltage rating that matches the system and grounding arrangement. The conductor cross-section must then be checked for continuous current, permissible voltage drop, fault current and protective-device operation.

Account for Installation Conditions

A cable in open air dissipates heat differently from one in conduit, buried soil or a crowded tray. Ambient temperature, soil thermal resistivity, burial depth, grouping and nearby heat sources can reduce allowable current.

Mechanical risk also matters. Armour, conduit or another protective method may be needed where the cable is buried, exposed to impact or installed in an industrial area.

Choose Materials and Construction

• Copper or aluminium conductor
• PVC, XLPE, rubber or project-specific insulation
• PVC, PE or low-smoke halogen-free outer sheath
• Screening for electromagnetic or electric-field control
• Steel tape or steel wire armour when specified
• Flame, smoke, halogen and fire-resistance performance required by the project

Prepare a Purchasable Specification

A complete description should state the applicable standard, voltage grade, conductor material, number of cores, nominal cross-section, insulation, screen, armour, sheath and required tests. Add drum length, quantity, marking and destination.

If the design is not final, request a technical data sheet before placing the order. Do not approve cable only from a photograph or a commercial nickname.