The low-voltage self-supporting cable (0.6/1 kV) is a type of bundled aerial cable in which the insulated aluminum phase, neutral, and street lighting conductors are twisted around a galvanized steel insulated messenger wire.
This assembly, known as Aerial Bundled Cable (ABC), can be installed suspended between poles and supports or mounted on building facades and walls.
Classification of Self-Supporting Cables
The classification of three-phase and single-phase self-supporting cables based on the number of conductors is as follows:
A) Three-phase self-supporting cable
Three phase conductors, one neutral conductor, one street lighting conductor, and one messenger wire.
Designation: 3×A + N + L + M
B) Single-phase self-supporting cable with lighting conductor
Designation: 1×A + N + L + M
C) Single-phase self-supporting cable without lighting conductor
Designation: 1×A + N + M
Where:
A = Cross-section of phase conductors
N = Cross-section of neutral conductor
L = Cross-section of street lighting conductor
M = Cross-section of messenger wire
Note 1: The lighting conductor may be omitted upon the customer’s request.
The conductors (phase, neutral, and lighting) are made of pure aluminum, while the messenger wire is made of galvanized steel. All conductors are insulated with black XLPE (Cross-Linked Polyethylene). After extrusion, the insulation is cross-linked under high steam temperature and pressure.
The cross-linking process significantly enhances the electrical and mechanical properties and improves resistance to ultraviolet (UV) radiation. In the self-supporting cable, the messenger wire bears all mechanical loads.
Identification of Conductors
Each phase conductor has longitudinal ridges on its surface for identification:
One ridge for phase R (or A)
Two ridges for phase S (or B)
Three ridges for phase T (or C)
The neutral conductor has uniformly distributed fine ridges (“thousand thorns”) around its insulation, the lighting conductor is smooth and without ridges, and the messenger wire is smooth and printed with the cable specifications.
Cross-section of 6-Core Self-Supporting Cable
In the following diagram, the index b represents the ridge width, h represents the ridge height, and a represents the distance between ridges.
