AAC conductor · 25 mm² nominal

ANT Conductor — Specification & Current Carrying Capacity

7/2.21 mm Al · 26.85 mm² total area · 6.63 mm overall diameter · 74 kg/km · 1.0930 Ω/km at 20 °C · 4.60 kN breaking load · about 130 A.

Short LT spans and urban distribution where corrosion resistance matters.

Full technical specification

Data basis: IS 398 and standard manufacturer catalogues. Individual manufacturers vary slightly — confirm against the supplier datasheet before final design.

Code nameANT
FamilyAAC
MaterialAll-aluminium stranded conductor (no steel core)
Stranding7/2.21 mm Al
Aluminium strands7 × 2.21 mm
Steel strandsNone
Aluminium area26.85 mm²
Steel area
Total area26.85 mm²
Nominal (trade) area25 mm²
Overall diameter6.63 mm
Approximate weight74 kg/km
DC resistance at 20 °C1.0930 Ω/km
Calculated AC resistance at 75 °C1.4020 Ω/km
Ultimate breaking load4.60 kN
Current carrying capacity130 A (standard basis)

Construction of ANT

ANT is built as 7/2.21 mm Al. All-aluminium stranded conductor (no steel core). With no steel core the whole cross-section conducts, giving the lowest resistance per mm² of any of the families, at the cost of breaking load. The total metallic area of 26.85 mm² and overall diameter of 6.63 mm set both the resistance and the wind/ice loading the structures must carry.

Where ANT is used

Short LT spans and urban distribution where corrosion resistance matters. At 130 A on the standard basis, a three-phase circuit of ANT carries roughly 2 MVA at 11 kV, 7 MVA at 33 kV and 30 MVA at 132 kV — useful as a first sanity check before detailed load flow.

Conditions behind the current rating

Ambient 40 °C, maximum conductor temperature 75 °C, cross-wind 0.61 m/s, solar radiation 1000 W/m², emissivity 0.9, absorptivity 0.8, outdoor overhead installation (IEEE 738 / IS 398 practice).

  • Wind is the single biggest variable. Removing it drops the rating of ANT from 129 A to 63 A in the cases above.
  • Raising the permitted conductor temperature increases the rating, but sag and long-term annealing of the aluminium set the practical ceiling — 75 °C continuous is the usual limit.
  • A weathered, dark conductor absorbs more sunlight but also radiates heat better; the standard 0.8 absorptivity / 0.9 emissivity pair is the conservative combination.
  • Terminations, jumpers and clamps often limit a line before the conductor does. Check the whole current path, not only the span.

Other AAC conductors

Calculators for this conductor