Current distribution in single-core cables connected in parallel

In Hong Kong buildings, large, parallel-connected single-core cables are often used to connect transformers to main low-voltage switchboards. As power consumption in buildings increases, overheating problems associated with such cable installations have become a concern. The paper investigates current distribution among parallel-connected single-core cables in a multi-phase distribution system. A general current-distribution prediction method is proposed and validated experimentally. The impact of cable, source and installation parameters, as well as the presence of a steel cable tray, is reported. The current distribution associated with the Hong Kong practice of parallel cable installations is evaluated, and recommendations for the design and installation are presented