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ACSR conductor · 420 mm² nominal

ZEBRA Conductor — Specification & Current Carrying Capacity

54/3.18 mm Al + 7/3.18 mm steel · 484.50 mm² total area · 28.62 mm overall diameter · 1621 kg/km · 0.0687 Ω/km at 20 °C · 130.32 kN breaking load · about 735 A.

220 kV and 400 kV bundled transmission lines.

Calculate ZEBRA ampacityCompare with other conductors

Full technical specification

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

Code nameZEBRA
FamilyACSR
MaterialAluminium strands over a 7-wire galvanised steel core
Stranding54/3.18 mm Al + 7/3.18 mm steel
Aluminium strands54 × 3.18 mm
Steel strands7 × 3.18 mm
Aluminium area428.90 mm²
Steel area55.60 mm²
Total area484.50 mm²
Nominal (trade) area420 mm²
Overall diameter28.62 mm
Approximate weight1621 kg/km
DC resistance at 20 °C0.0687 Ω/km
Calculated AC resistance at 75 °C0.0881 Ω/km
Ultimate breaking load130.32 kN
Current carrying capacity735 A (standard basis)

Construction of ZEBRA

ZEBRA is built as 54/3.18 mm Al + 7/3.18 mm steel. Aluminium strands over a 7-wire galvanised steel core. The steel core takes most of the mechanical tension so the aluminium can be sized purely for current, which is what lets ACSR span long distances between towers. The total metallic area of 484.50 mm² and overall diameter of 28.62 mm set both the resistance and the wind/ice loading the structures must carry.

Where ZEBRA is used

220 kV and 400 kV bundled transmission lines. At 735 A on the standard basis, a three-phase circuit of ZEBRA carries roughly 14 MVA at 11 kV, 42 MVA at 33 kV and 168 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 ZEBRA from 743 A to 423 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 ACSR conductors

SQUIRREL

6/2.11 mm Al + 1/2.11 mm steel · 115 A

WEASEL

6/2.59 mm Al + 1/2.59 mm steel · 150 A

FERRET

6/3.00 mm Al + 1/3.00 mm steel · 185 A

RABBIT

6/3.35 mm Al + 1/3.35 mm steel · 208 A

MINK

6/3.66 mm Al + 1/3.66 mm steel · 234 A

RACCOON

6/4.09 mm Al + 1/4.09 mm steel · 270 A

Calculators for this conductor

Conductor Current Capacity Calculator

Recalculate ZEBRA ampacity for your own weather and temperature limit.

Voltage Drop Calculator

Check the drop over the span length you are planning.

AWG to sq mm Converter

Translate the area into American gauge sizes.

Transformer Sizing Calculator

Match the feeder to the transformer it supplies.

AC Cable Sizing Calculator

For the insulated cable portions of the same circuit.

Wire Gauge Chart

AWG to mm² reference table.