Conductor cross- sectional area | Reference method 4 (enclosed in conduit in thermally insulating wall etc) | Reference method 3 (enclosed in conduit on a wall or in trunking etc) | Reference method 1 (clipped direct) | Reference method 11 (on a perforated cable tray, horizontal or vertical) | Reference method 12 (free air) |
|
2 cables, single- phase a.c. or d.c. |
3 or 4 cables, 3-phase a.c. |
2 cables, single- phase a.c. or d.c |
3 or 4 cables, 3-phase a.c. |
2 cables, single- phase a.c. or d.c. flat and touching |
3 or 4 cables, 3-phase a.c. flat and touching or trefoil |
2 cables, single- phase a.c. or d.c. or flat and touching |
3 or 4 cables, 3-phase a.c. flat and touching or trefoil | 2 cables, single- phase a.c. or d.c. or 3 c ables three phase | 2 cables, single- phase a.c. or d.c. or 3 cables three phase |
3 cables, trefoil 3- phase a.c. |