In A B Cables, there are three insulated cores and one insulated neutral core (optional)
laid around a bare or covered messenger wire, which carries the load of the cable. There can be one additional power core
for street lighting.
Power
and Neutral Cores: Here, the conductor is composed of H2 or H4 grade Aluminium of Class 2 grade to IS: 8130/84. Popular
sizes are 16mm2 to 95mm2. Again, insulation can be either cross linked Polyethylene or Polyethylene.
Messenger Conductor: These
are made of either galvanized Steel or Aluminium alloys.
Core
Identification: Either by number printing or by ridges on insulated cores.
In comparison to bare overhead lines, aerial bunched cable has very
high degree of safety and reliability due to the conductors being insulated with the best dielectric medium. This ensures
good protection against ground and line faults leading to considerable increase in system efficiency as against bare overhead
lines. The problem of free-clearance is also minimized.
Aerial bunched cable system is specially suited in limited space conditions like densely
populated areas where laying of underground cables is impossible or extremely expensive.
