IEC TR 62470:2011 pdfダウンロード。Guidance on techniques for the measurement of the coefficient of friction (COF) between cables and ducts 1 Scope and object This technical report describes three techniques to measure the coefficient of friction (COF) between cables and ducts. For a given technique, cable construction, installation method (pulling, pushing, or blowing), and duct size, the relative values of the COF can give some indication as to the relative ease of installation. The techniques can be used for traditional cables and ducts (see IEC 60794-3-1 0) as well as for microduct cables and microducts (see IEC 60794-5). A fibre or...