AB CABLE APPLICATIONS

Aerial Bunched Cable (ABC cable) is an innovative concept for overhead power distribution as compared to the conventional bare conductor overhead distribution system. It uses several insulated phase conductors bundled tightly together, usually with a bare neutral conductor. This contrasts with the traditional practice of using uninsulated conductors separated by air gaps demanded by changes in urban development plan.

The main objections to the traditional design are that the multiple conductors are considered messy, and external forces (such as high winds) can cause them to touch and short circuit. The resultant sparks have been a cause of bushfires in drier climates. With ABC, a simultaneous disconnection of all conductors is more likely.

In moister climates, tree growth is a significant problem for overhead power lines. Aerial bundled cables will not arc over if touched by tree branches. Although persistent rubbing is still a problem, tree-trimming costs can be reduced.

It provides higher level of safety and reliability, lower power losses and ultimate system economy by reducing installation, maintenance and operative cost. This system is ideal for rural distribution and it is especially perfect for installation in difficult terrains such as hilly areas, forest areas, coastal areas etc. ABC is also considered to be ideal for power distribution in congested urban areas with narrow lanes and by-lanes.

Advantages

• Less maintenance.
• Simpler installation, as crossbars and insulators are not required.
• Less cluttered appearance.
• Electricity theft is made harder and more obvious to detect.
• Relative immunity to short circuits caused by external forces (wind, fallen branches), unless they abrade the insulation.
• Can be installed in a narrower right-of-way.
• At junction poles, insulating bridging wires are needed to connect non-insulated wires at either side.
   ABC can dispense with one of these splices.
• It improves the safety and reliance of electrified wire netting.
• Less risk of a neutral-only break from tree or vehicle damage, increasing safety with TNC-s systems.
• Can stand in close proximity to trees and will not generate sparks if touched.

Self supporting LV ABC system sample network layout

Service - 2x16 mm²
Bare line - 4x95 mm²
LV-ABC line - 4x95 mm²
Cable - 4x150 mm²
Service - 4x16 mm²

LV accessories application points

1. Anchoring and cable connection
2. Joints
3. Suspension deviation 300-600
4. Main suspension and service line tap
5. Anchoring and connection to bare overhead line
6. Bare main service line tap

Specification

IEC/ BSEN/ DIN/ BS/ NFC/ IS/ ASTM or any other international specification to meet the buyers requirements.

Product Details

The basic construction of Aerial Bunched Cable is as follows :

3 power cores consisting of standard aluminium conductors, insulated with Aerial Bundled Cable XLPE insulation
+ One sheath lighting aluminium conductor with XLPE insulation(optional)
+ One messenger Al-alloy conductor (bare or covered)

The messenger conductor can be of galvanised steel wire also.

A. It acts as load bearing wire.
B. It acts as earth or neutral conductor.

The Cores

Each phase core is marked with numerals 1, 2 or 3 and with one rib, two ribs or three ribs to denote the three phases. These ribs facilitate identification of the phases and the neutral even when numerals cannot be properly seen due to bad light. To expedite ascertaining the approximate length of cable left on the drum, sequential length marking is done on one active core at one meter intervals. Drum lengths start at any number with the lowest number near the end at the drum barrel. The cores are laid up in a bundle. Rating of LV ABC is based on a conductor operating temperature of 80º C.

Conductor

Phase conductors are manufactured from high conductivity high purity aluminium of Grade 1350 and are stranded circular and compacted. Neutral cum Messenger is made out of heat treated aluminium alloy wires of 6201 Grade and are stranded circular. Based on extensive development testing and production research the surface of the conductor is specially treated to improve adhesion of the insulation to the conductor. This is important because the installed cable tension is completely provided by this 'adhesion' or 'friction' between the conductor and the insulation.

Types of LV-ABC lines

LV-ABC Lines with insulated neutral messenger

LV-ABC Lines with insulated neutral messenger wire, also known as 'French System' consist of 3 insulated aluminium phase conductors and 1 neutral insulated messenger made of aluminium alloy (usually 6201). The system can incorporate 1 or 2 additional insulated aluminium conductors with cross sections of 16mm sq. or 25mm sq. as pilot wires or for steel lighting. The mechanical strength and nominal cross section of the 3 phase conductors are identical. The neutral conductor acts as the suspension wire and has a higher mechanical strength.

Self-supporting LV-ABC Lines

Self-supporting LV-ABC Lines consist of 4 insulated aluminium conductors with identical mechanical strength and nominal cross section. The system can incorporate 1 or 2 additional insulated aluminium conductors with cross sections of 16mm sq. or 25mm sq. as pilot wires or for steel lighting. Loading the cable puts equal strain on all 4 conductors.

LV-ABC Lines with Bare Neutral Messenger

LV-ABC Lines with bare neutral messenger wire, also known as 'Finnish System', consist of 3 insulated aluminium phase conductors and 1 neutral messenger made of aluminium alloy without insulation. The system can incorporate 1 or 2 additional insulated aluminium conductors with cross sections of 16mm sq. or 25mm sq. as pilot wires or for steel lighting. The mechanical strength and nominal cross section of the 3 phase conductors are identical. The neutral conductor acts as the suspension wire and has a higher mechanical strength.

Service line

The service line for the three LV-ABC systems is usually of the self-supporting type. They consist of 2 to 4 factory bundled insulated aluminium conductors with cross sections of 16mm sq, 25mm sq, or 35mm sq.


Dimension of LVABC lines with insulated neutral messenger

Dimensions of phase conductors

-*defined for ambient temperature of 300 C and max conductor temperature of 900 C

Dimension of neutral messenger conductors

K number of public lighting conductors (K can equal to 0,1,2 or 3)

Our state-of-the-art products comply with the various International Specifications like IS (Indian), BS-EN (European), ASTM (USA), CSA (Canadian), IEC etc. Besides, we are a reputed Export House recognized by the Government of India.

Dimension of LVABC lines with self-supporting messenger

Dimensions of neutral messenger conductors

*defined for ambient temperature of 350 C and max conductor temperature of 800 C

Dimension of LV-ABC lines with bare neutral messenger

*defined for ambient temperature of 250 C and max conductor temperature of 700 C

Dimension of neutral messenger conductors

K number of public lighting conductors (K can equal to 0, 1, 2 or 3)