Chapter A General rules of electrical installation design

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G8
G - Sizing and protection of conductors
Fig. G9 : Erection of wiring systems (table 52-2 of IEC 60364-5-52)
2 Practical method for determining
the smallest allowable crosssectional
area of circuit conductors
Possible methods of installation for different situations:
Different methods of installation can be implemented in different situations. The
possible combinations are presented in Figure G9.
The number given in this table refer to the different wiring systems considered.
(see also Fig. G10)
Situations Method of installation
Without With Conduit Cable trunking Cable Cable ladder On Support
fixings fixings (including ducting cable tray, insulators wire
skirting trunking,
flush floor trunking)
cable brackets
Building voids 40, 46, 0 15, 16, – 43 30, 31, 32, – –
15, 16 41, 42 33, 34
Cable channel 56 56 54, 55 0 44, 45 30, 31, 32,
33, 34
– –
Buried in ground 72, 73 0 70, 71 – 70, 71 0 –
Embedded in structure 57, 58 3 1, 2,
59, 60
50, 51, 52, 53 44, 45 0 – –
Surface mounted – 20, 21 4, 5 6, 7, 8, 9, 12, 13, 14 6, 7, 30, 31, 32, 36 –
22, 23 8, 9 33, 34
Overhead – – 0 10, 11 – 30, 31, 32
33, 34
36 35
Immersed
– Not permitted.
80 80 0 – 0 0 – –
0 Not applicable, or not normally used in practice.
Schneider Electric - Electrical installation guide 2008