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The standard is the international benchmark for Low-voltage Busbar Trunking Systems (BTS) , commonly known as busways. It establishes the requirements for design, construction, performance, and verification for these power distribution systems. Key Technical Aspects of IEC 61439-6 iec 61439-6 pdf
If the busbar passes through a fire compartment, Clause 8.7 requires a tested barrier. Without it, fire can travel through the busway opening. The most authoritative source
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, allowing manufacturers three equivalent methods to prove compliance: Comparison with a reference design, or Assessment (calculation). IEC 61439-6 - iTeh Standards iec 61439-6 pdf