Understanding harmonised cable codes

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An effort by CENELEC (a European standards committee) to harmonise the classification of cables had lead to a coding system that you will often see used to specify the detailed characteristics of a cable or flex (more commonly used for the latter it seems). These designations are often written in the form H05RN-F or H05BN-F etc. While they actually give you lots of technical detail about the cable in a very short code, they do take quite a bit of deciphering!

The code

The codes break down into three parts:

Part 1 of the Designation

Table 1a gives you the standards compliance and maximum nominal voltage

Symbol Conformance to Standards
H Cable conforms with the harmonised standards
A Cable conforms with a Recognised National Type, listed in a Supplement to the harmonised standards

Table 1b Gives the voltage rating of the cable

Symbol Voltage Rating, Single/3Ph
01 >= 100/100V to < 300/300V
03 300/300V
05 300/500V
07 450/750V

Part 2 of the Designation

Table 2a gives you the insulating material and the designation of any non metallic sheath. Hence you need two sets of letters from this table, the first to describe the insulator used for the conductors themselves, and the second to tell you about the material used for the overall sheath.

Symbol Material
B Ethylene-propylene rubber (Continuous operation up to 90°C)
G Ethylene-vinyl-acetate
J Glass-fibre braid
M Mineral
N Polychloroprene (or equivalent material)
N2 Special polychloroprene compound for covering of welding cables according to HD 22.6
N4 Chlorosulfonated polyethylene or chlorinated polyethylene
N8 Special water resistant polychloroprene compound
Q Polyurethane
Q4 Polyamide
R Ordinary ethylene propylene rubber or equivalent synthetic elastomer for a continuous operating temperature of 60ºC
S Silicone rubber
T Textile braid, impregnated or not, on assembled cores
T6 Textile braid, impregnated or not, on individual cores of a multi-core cable
V Ordinary PVC
V2 PVC compound for a continuous operating temperature of 90ºC
V3 PVC compound for cables installed at low temperature
V4 Cross-linked PVC
V5 Special oil resistant PVC compound
Z Polyolefin-based cross-linked compound having low level of emission of corrosive gases and which is suitable for use in cables which, when burned, have low emission of smoke
Z1 Polyolefin-based thermoplastic compound having low level of emission of corrosive gases and which is suitable for use in cables which, when burned, have low emission of smoke
So for example

With H05RN-F, the R tells you the wires are insulated in Ordinary ethylene propylene rubber, 
and the N that the overall insulation is Polychloroprene


Table 2b gives a number of possible metallic coverings:

Symbol Sheath, concentric conductors and screens
C Concentric copper conductor
C4 Copper screen as braid over the assembled cores


Table 2c for some special constructions of components of the cable:

Symbol Sheath, concentric conductors and screens
D Strain-bearing element consisting of one or more textile components, placed at the centre of a round cable or distributed inside a flat cable
D5 Central heart (non strain-bearing for lift cables only)
D9 Strain-bearing element consisting of one or more metallic components, placed at the centre of a round cable or distributed inside a flat cable


Next, you may get any of the following tacked onto the ends of codes from tables a to c above:

Table 2d Special constructions of whole cable

Symbol Special construction
No Symbol Circular construction of cable
H Flat construction of “divisible” cables and cores, either sheathed or non-sheathed
H2 Flat construction of “non-divisible” cables and cores
H6 Flat cable having three or more cores, according to DH 359 or EN 50214
H7 Cable having a double layer insulation applied by extrusion
H8 Extensible lead


Next an optional group for specifying the conductor material. This is only required for non copper conductors and will follow a dash.

Table 2e Conductor material

Symbol Conductor material
No Symbol Copper
-A Aluminium


Lastly, Again these follow after a dash (the same one as that used to specify aluminium conductors above if present!)

Table 2f Conductor form

(note for cables with two forms of conductor, the specification applies to the phase conductor only)

Symbol Conductor form
-D Flexible conductor for use in arc welding cables to HD 22Part 6 (flexibility different from Class 5 of HD 383)
-E Highly flexible conductor for use in arc welding cables to HD22 Part 6 (flexibility different from Class 6 of HD 383)
-F Flexible conductor of a flexible cable or cord (flexibility according to Class 5 of HD 383)
-H Highly flexible conductor of a flexible cable or cord (flexibility according to Class 6 of HD 383)
-K Flexible conductor of a cable for fixed installations (unless otherwise specified, flexibility according to Class 5 of HD 383)
-R Rigid, round conductor, stranded
-U Rigid round conductor, solid
-Y Tinsel conductor (Tinsel conductors are used in flexes for small appliances were normal stranded flex would be likely to fatigue and break - its made with a conductive foil wrapped around a supporting textile or plastic core to provide the tensile strength)

Part 3 of the Designation

Table 3 Number of cores and the nominal cross sectional area of each core.

Symbol Number and size of conductors
(number) Number, n of cores
X Times, where a green/yellow core is not included
G Times, when a green/yellow core is included
(number) Nominal cross-section, s, of conductor in mm²

(Note an N after the number of cores indicates the cores are identified by numbers rather than or in addition to colours)

Y For a tinsel conductor where the cross-section is not specified


Fitting all the bits together

1 2 3 4 5 6 7 8 9 10 11
Part 1 Part 2 Part 3
Related
standard
Rated
voltage
Insulating
material
Metallic
coverings (2)
Non-metallic
sheath (2)
Constructional
components and
special constructions
Conductor
material
Conductor
forms
Number of cores Times Conductor
size mm²
Symbols according to tables
1a 1b 2a 2b 2a 2c and 2d 2e 2f 3
H 01 B C B D3 No -D 1 X Y
D5 symbol: -E 2 0.5
A 03 G C4 G copper -F 3 G
----- -H 4 0.75
05 J J No symbol: -A -K 5
circular -R etc 1
07 M construction of -U
cable -Y 1.5
N, N4 N,N2,N4,N8
H 2.5
Q, Q4 H2
H6 4
R R H7
H8 6
S S
10
T, T6
16
V, V2, V, V2, V3,
V3, V4 V4, V5 25
Z, Z1 Z, Z1 etc

(1) If two or more symbols listed in the same column need to be used in a given designation, they shall follow each other in their radial sequence starting from the core axis or cable axis.

(2) The symbols might change their position in the designation with respect to the construction of the cable

British CMA code equivalents

The British CMA codes often quoted by cable suppliers, are needless to say different to the harmonised codes. THe following table illustrates some of the common codes and their equivalent in harmonised form:

CMA Code Harmonised Code Applicable standard Comments
2183Y H03VV-F Light duty 3 Core flex
6242BH H05V4Z1-U BS7211:1998 Table 7 Twin and Earth, Low Smoke Zero Halogen (LS0H)
6242Y H05VV-U Twin and Earth

See Also