> ElectricalDesign > References > BS7671 > Tables > Table 4A2 - Schedule of Installation Methods of cables (including reference methods) for determining current-carrying capacity

Table 4A2 - Schedule of Installation Methods of cables (including reference methods) for determining current-carrying capacity

Keywords
BS7671, table 4A2, cable installation methods, current-carrying capacity, reference methods, cable, multicore cable, single-core cable, non-sheathed cables
Abstract
TiSoft ElectricalDesign logo

ElectricalDesign

ElectricalDesign helps you design any building's electrical installation, make all the necessary calculations ensuring code compliance, and produce a variety of drawings, floorplans, schematics and reports.

Try it

Cable sizing

A practical example of cable size calculation along with the methodology and the steps required with references to the standards.

See example

The following table shows the cable installation methods according to the Standard BS7671. These methods are used by ElectricalDesign to perform the cable sizing calculation.

The illustrations are not intended to depict actual product or installation practices but are indicative of the method described.

The installation and reference methods stated are in line with IEC. However, not all methods have a corresponding rating for all cable types.

Installation method Reference Method to be used to determine current-carrying capacity
Number Examples Description
1 BS7671, Table 4A2, Non-sheathed cables in conduit in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K Non-sheathed cables in conduit in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K c A
2 BS7671, Table 4A2, Multicore cable in conduit in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K Multicore cable in conduit in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K c A
3 BS7671, Table 4A2, Multicore cable direct in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K Multicore cable direct in a thermally insulated wall with an inner skin having a thermal conductance of not less than 10 W/m²K c A
4 BS7671, Table 4A2, Non-sheathed cables in conduit on a wooden or masonry wall or spaced less than 0.3 × conduit diameter from it Non-sheathed cables in conduit on a wooden or masonry wall or spaced less than 0.3 × conduit diameter from it c B
5 BS7671, Table 4A2, Multicore cable in conduit on a wooden or masonry wall or spaced less than 0.3 × conduit diameter from it Multicore cable in conduit on a wooden or masonry wall or spaced less than 0.3 × conduit diameter from it c B
6
7
BS7671, Table 4A2, Non-sheathed cables in cable trunking on a wooden or masonry wall <br/>6 - run horizontally <br />7 - run vertically Non-sheathed cables in cable trunking on a wooden or masonry wall
6 - run horizontally b
7 - run vertically b, c
B
8
9
BS7671, Table 4A2, Multicore cable in cable trunking on a wooden or masonry wall Multicore cable in cable trunking on a wooden or masonry wall
8 - run horizontally b
9 - run vertically b, c
B*
10
11
BS7671, Table 4A2, Non-sheathed cables Non-sheathed cables run in suspended cable trunking b B
Multicore cable in suspended cable trunking b B
12 BS7671, Table 4A2, Non-sheathed cables run in mouldings Non-sheathed cables run in mouldings c, e A
13
14
Deleted by BS 7671:2008 Amendment No 1
15 BS7671, Table 4A2, Non-sheathed cables run in conduit or single-core or multicore cable in architrave Non-sheathed cables run in conduit or single-core or multicore cable in architravec, f A
16 BS7671, Table 4A2, Non-sheathed cables run in conduit or single-core or multicore cable in window frames Non-sheathed cables run in conduit or single-core or multicore cable in window frames c, f A
20 BS7671, Table 4A2, Single-core or multicore cables: Single-core or multicore cables:
- fixed on (clipped direct) or spaces less than 0.3 × cable diameter from a wooden or masonry wall c
C
21 BS7671, Table 4A2, Single-core or multicore cables: Single-core or multicore cables:
- fixed directly under a wooden or masonry ceiling
C
(higher than standard ambient temperatures may occur with this installation method)
22 BS7671, Table 4A2, Single-core or multicore cables: Single-core or multicore cables:
- spaced from a ceiling
E, F or G*
(higher than standard ambient temperatures may occur with this installation method)
23 Not used
30 BS7671, Table 4A2, Single-core or multicore cables: Single-core or multicore cables:
- on unperforated tray
run horizontally or vertically c, h
C with item 2
of Table 4C1

TiSoft,