IEC 61439 mandates that all assemblies must withstand the mechanical and thermal stresses of short-circuit currents. The assembly's short-circuit withstand current rating (Icw) represents the maximum current the assembly can safely carry for a specified duration (typically 1 second). IEC 61439 is a standard developed by the International Electrotechnical Commission (IEC) that covers design verification for low-voltage electrical products and assemblies. The current rating is calculated from the conductor cross-sectional area, material (copper or aluminium), and maximum. Rated voltage does not exceed 1 000 V AC or 1500 V DC. Generation, transmission, distribution and control of electric energy. Electrical equipment of. Guide to Low Voltage Busbar Trunking Systems Verified to BS EN 61439-6 Guide to Low Voltage Busbar Trunking Systems Verified to BS EN 61439-6 November 2014 Guide to Low Voltage Busbar Trunking Systems Verified to BS EN 61439-6 Companies involved in the preparation of this Guide Acknowledgements. For busbar sizing, the primary references are IEC 61439 (for low-voltage switchgear and controlgear assemblies) and IEC 60287 (for current-carrying capacity of cables). These standards specify the parameters that should be considered when sizing busbars, including current rating, short-circuit. The Icw test evaluates the resilience of the busbar system to electrodynamic forces during a short circuit. The current applied in the test peaks at 2.
