According to IEC 60287-2-1 for a single group.
Coefficient f is used for channel acc. Heinhold. The values for one single cable, three cables spaced horizontally and three cables trefoil are given in the book 'Kabel und Leitungen für Starkstrom' by L. Heinhold, 5th edition 1999. There are no values for 2 cables nor touching cables and no difference between horizontal and vertical laying. In comparison with the value for trefoil being 2/3, the value for 3 objects touching is assumed to be 5/6 and for 2 objects touching is assumed to be 8/9.
Id | Installation | factor Z | factor E | factor g | factor f | Info |
---|---|---|---|---|---|---|
1 | 1 single object | 0.21 | 3.94 | 0.6 | 1.0 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.3D |
2 | 2 objects touching, horizontal | 0.29 | 2.35 | 0.5 | 0.888 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D |
3 | 2 objects spaced, horizontal (clearance > 0.75D) | 0.21 | 3.94 | 0.6 | 1.0 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.3D, hor. clearance ≥ 0.75D |
4 | 2 objects touching, vertical | 1.42 | 0.86 | 0.25 | 0.888 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D |
5 | 2 objects spaced, vertical (clearance > D) | 0.75 | 2.8 | 0.3 | 1.0 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D, ver. clearance ≥ D |
6 | 3 objects touching, horizontal | 0.62 | 1.95 | 0.25 | 0.833 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D |
7 | 3 objects spaced, horizontal (clearance > 0.75D) | 0.21 | 3.94 | 0.6 | 1.0 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.3D, hor. clearance ≥ 0.75D |
8 | 3 objects touching, vertical | 1.61 | 0.42 | 0.2 | 0.833 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ D |
9 | 3 objects spaced, vertical (clearance > D) | 1.31 | 2.0 | 0.2 | 1.0 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D, ver. clearance ≥ D |
10 | 3 objects touching trefoil | 0.96 | 1.25 | 0.2 | 0.667 | Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5D |