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60°C Thermosetting Insulated Flexible Cables With Sheath, Non Armoured (COPPER CONDUCTORS)
Tables Apply to: Flexible Cables (also see tables - (Flexible Cords, Non Armoured) and (90°C and 180°C Thermosetting Insulated Flexible Cables With Sheath)
CURRENT-CARRYING CAPACITY (amperes)
|Conductor Cross Sectional Area||Single-phase a.c. or d.c.||Three-phase a.c.||Single-phase a.c. or d.c.|
|1 two-core cable,with or without protective conductor||1 three-core, four core or five core||2 single-core cable|
- The current ratings tabulated are for cables in free air but may also be used for cables resting on a surface. If the cable is to be wound on a drum on load the ratings should be reduced in accordance with Note 2 below and for cables which may be covered, Note 3 below.
- Flexible cables wound on reeling drums
- The current ratings of cables used on reeling drums are to be reduced by the following factors:
a) Radial type drum | ventilated: 85% | unventilated: 75%.
b) Ventilated cylindrical type drum, 1 layer of cable: 85%, 2 layers of cable: 65%, 3 layers of cable: 45%, 4 layers of cable: 35%
- A radial type drum is one where spiral layers of cable are accommodated between closely spaced flanges; if fitted with solid flanges the ratings given above should be reduced and the drum is described as non-ventilated. If the flanges have suitable apertures the drum is described as ventilated.
- A ventilated cylindrical cable drum is one where layers of cable are accommodated between widely spaced flanges and the drum and end flanges have suitable ventilating apertures.
- Where cable may be covered over or coiled up whilst on load, or the air movement over the cable restricted, the current rating should be reduced. It is not possible to specify the amount of reduction but the table of rating factors for reeling drums can be used as a guide.
VOLTAGE DROP (per ampere per metre)
|Conductor Cross Sectional Area||Two-core cable d.c.||Two-core cable, single-phase a.c. ||1 three-core, four-core or five core cable, three-phase a.c.||2 single-core cables, touching|
| || ||r||x||z||r||x||z|| ||r||x||z|
NOTE: *A larger voltage drop will result if the cables are spaced
DISCLAIMER: This information has been supplied in good faith and the upmost care has been taken to ensure the data is accurate in it's derivation from BS7671.
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However, this information should not be considered as a substitute for BS7671, which should always be referred to. It remains the responsibility of the user to ensure all data and assumptions are correct and that any cable used is suitable for its intended purpose.