# Installation in air

According to IEC 60287-2-1 Ed.2.0 for a single group of cables and IEC 60287-2-2 Ed.1.0 for more than one group of cables.

The wall clearance \$e_{wall}\$ is the distance between the closest cable to the wall and the object clearance \$e_{hor}\$ and \$e_{ver}\$ is the horizontal and vertical distance between two objects. Both values are relative to the outer diameter of the object.

There are discrepancies between the two standards IEC 60287-2-1 and -2-2, we use -2-1 when possible:

• For one object near a wall, the -2-1 considers the object free from wall at a clearance factor of 0.3 whereas the -2-2 considers the factor 0.5 and mentiones this to be valid also for a surface below the object.
• For two objects spaced horizontally, the standard -2-1 considers the objects spaced at a clearance factor of 0.75 whereas the -2-2 considers the factor 0.5.
• For two and three objects spaced vertically, the standard -2-1 considers the objects spaced at a clearance factor of 1 whereas the -2-2 considers the factor 0.5 plus an equation (refer to \$h_{lg}\$) between 0.5 and 4.

Symbol
\$inst_{air}\$
Choices
IdInstallationfactor Zfactor Efactor gwall clearanceobject clearanceInfo
11 single object0.213.940.60.30Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.3⋅D
22 objects touching, horizontal0.292.350.50.50Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D
32 objects spaced, horizontal0.213.940.60.50.75Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D, horizontal clearance 0.75⋅D
42 objects touching, vertical1.420.860.250.50Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D
52 objects spaced, vertical0.752.80.30.51.0Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D, vertical clearance D
63 objects touching, horizontal0.621.950.250.50Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D
73 objects spaced, horizontal0.213.940.60.50.75Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D, horizontal clearance 0.75⋅D
83 objects touching, vertical1.610.420.21.00Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ D
93 objects spaced, vertical1.312.00.20.51.0Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D, vertical clearance D
103 objects touching trefoil0.961.250.20.50Installation on non-continuous brackets, ladder supports or cleats, clearance to wall ≥ 0.5⋅D
111 single object on wall1.690.630.2500Clipped direct to a vertical wall, D ≤ 0.08 m
123 objects in trefoil on wall0.940.790.200Clipped direct to a vertical wall, D ≤ 0.08 m
13More than one group of cables0.961.250.2--The arrangement of more than one group of cables is limited to configurations in IEC 60287-2-2
14More than one multi-core cable0.213.940.6--The arrangement of more than one multi-core cable is limited to configurations in IEC 60287-2-2
Image
IEC standard 60287-2-1 Ed. 2.0 (2015) Table 2