90°C and 180°C Thermosetting Insulated Flexible Cables with Sheath, Non-Armoured (Copper Conductors)
Current-carrying Capacity (amperes):
Ambient Temperature: 30°C
Conductor Operating Temperature: 90°C
|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
|2 single-core cables, touching|
Rating Factor for Ambient Temperature
|90°C Thermoplastic or Thermosetting Insulated Cords:|
|180°C Thermosetting Insulated Cords:|
|Ambient Temperature:||35°C to 90°C||95°C||100°C||105°C||110°C||150°C||120°C||125°C||130°C||135°C|
- 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 b) Ventilated cylindrical type drum
ventilated: 85% 1 layer of cable: 85%
unventilated: 75% 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.
- For 180oC cables, the rating factors for ambient temperature allow a conductor operating temperature up to 150oC. Consult the cable manufacturer for further information.
- Where it is intended to connect the cables in this table to equipment or accessories designed to operate at a temperature lower than the maximum operating temperature of the cable, the cables should be rated at the maximum operating temperature of the equipment or accessory (see Regulations 512.1.5).
- Where it is intended to group a cable in this table with other cables, the cable should be rated at the lowest of the maximum operating temperatures of any of the cables in the group (see Regulations 512.1.5).