Historical
IEC 60439-2 Ed. 3.1 b:2005
Low-voltage switchgear and controlgear assemblies - Part 2: Particular requirements for busbar trunking systems (busways)
Applies to busbar trunking systems intended to supply luminaires through tap-off units but does not apply to supply track systems in accordance with IEC Publication 570.
International Electrotechnical Commission [iec]