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Covered Conductor (MVCC) Selection Guide: 11 kV to 132 kV

Where covered conductors beat bare lines and ABC, what the construction layers do, and the standards that govern them.

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A covered conductor is an overhead line conductor with an insulating XLPE covering bonded over it. It is not a fully insulated cable — but the covering is enough to stop the faults that dominate overhead-line outages: conductor clash in wind, tree branches, creepers, birds and animals.

When MVCC is the right choice

  • Lines through forest, vegetation and wildlife corridors — transient tree contact stops tripping the line.
  • Congested residential and roadside routes, and road/rail/river crossings.
  • Coastal, polluted and high-wind zones — the anti-tracking outer layer resists salt, humidity and pollution.
  • Where right-of-way is tight: phase spacing can be reduced, cutting tower costs.

Construction (five layers)

  1. Stranded, longitudinally water-blocked conductor — AAAC, ACSR, ACSS or AL59 ACS
  2. Extruded semi-conducting screen
  3. Inner XLPE insulation (carbon-free)
  4. Outer UV-protected, anti-tracking black XLPE/HDPE
  5. All three polymer layers co-extruded and bonded

Ratings and standards

APAR covered conductors are available at 11, 22, 33, 66, 110 and 132 kV, in 100–400 mm², manufactured to SS-EN 50397-1, BS EN 50182, IS 398-2, IS 398-4 and IEC 61089, and type tested at CPRI Bengaluru and ERDA Vadodara. Standard operation is up to 95°C; the AL59 ACS conductor runs to 105°C and carries 15–20% more current than ACSR at the same sag.

Spans of 60–70 m are self-supporting — unlike ABC, no messenger carries the weight. Accessories (piercing connectors, clamps, sleeves) comply with EN 50397-2. Details on the covered conductors product page.