1. Cable shall be laid through pipes in the insulation wall:
The wall is composed of weatherproof outer strong skin, insulation layer and wood with heat transfer coefficient of 10W/m2K or similar wood inner wall skin. The wire tube is fixed close to the inner wall, but not necessarily touched. Imagine that the heat of the cable escapes only through the inner wall. The cable pipe can be metal or plastic.
2. The cable shall be directly placed inside the insulation wall:
Similar to 1, only with multi-core cable instead of conduit.
3. Wire pipe shall be laid on the wall:
Fix the wire tube so that the gap between the wire tube and the wall is less than 0.3 times the diameter of the wire tube.
4. Cable laying on the wall:
The cable is fixed so that the gap between the cable and the wall is less than 0.3 times the cable diameter.
5. Cable laying on floor or ceiling:
It’s similar to 4. The rated value for cable laid on the ceiling is slightly less than that for cable laid on the wall or floor.
6. Cables buried in the ground:
The cable touched the soil for laying. Tabular flow refers to soil thermal resistance rate of 2.5K·m/W and buried depth of 0.7m.
7. Cable laying in the conduit:
The cable is threaded into a non-metallic conduit in direct contact with the soil. The tabular flow corresponds to a soil thermal resistance rate of 2.5k ·m/W and a buried depth of 0.7m. For multi-core cables, these ratings may also be used if the cable is threaded in a metal tube.
8. Cable in free air:
The cable is supported in such a way that all heat is not prevented from escaping. Heat from the sun and other sources should be taken into account. And be careful not to block natural air convection. In fact, a gap of 0.3 times the cable’s outside diameter between the cable and any adjacent surface is sufficient to allow for a carrying rate suitable for free air conditions.
9. Cable tray:
The perforated tray has regular holes arranged to facilitate the use of cable fixing screws. If the holes occupy less than 30% of the surface area, the tray shall be considered as a non-porous tray.
10.The ladder was:
The structure produces minimal resistance to the airflow around the cable, that is, the area of the supporting metal under the cable is less than 10% of the plane area.
11. Wire clip and hook:
Cable support, which supports the cable at regular intervals along the length of the cable and essentially allows free circulation of air around the cable.