ACSR conductors are specified by codeword rather than by size, and every Indian utility specification uses the same animal-name ladder. What varies — and what causes real arguments at inspection — is which part of IS 398 the numbers came from.
The table
| Codeword | Nominal Al area mm² | Aluminium stranding | Steel stranding | Overall dia mm | Approx. mass kg/km | Max DC R at 20 °C Ω/km | Rated strength kN |
|---|---|---|---|---|---|---|---|
| Mole | 10 | 6 × 1.50 | 1 × 1.50 | 4.50 | 43 | 2.780 | 3.97 |
| Squirrel | 20 | 6 × 2.11 | 1 × 2.11 | 6.33 | 85 | 1.394 | 7.61 |
| Gopher | 25 | 6 × 2.36 | 1 × 2.36 | 7.08 | 106 | — | — |
| Weasel | 30 | 6 × 2.59 | 1 × 2.59 | 7.77 | 128 | 0.9289 | 11.12 |
| Ferret | 40 | 6 × 3.00 | 1 × 3.00 | 9.00 | 171 | — | — |
| Rabbit | 50 | 6 × 3.35 | 1 × 3.35 | 10.05 | 214 | 0.5524 | 18.25 |
| Mink | 60 | 6 × 3.66 | 1 × 3.66 | 10.98 | 255 | — | — |
| Beaver | 70 | 6 × 3.99 | 1 × 3.99 | 11.97 | 303 | — | — |
| Raccoon | 80 | 6 × 4.09 | 1 × 4.09 | 12.27 | 319 | 0.3712 | 26.91 |
| Cat | 95 | 6 × 4.50 | 1 × 4.50 | 13.50 | 386 | — | — |
| Dog | 100 | 6 × 4.72 | 7 × 1.57 | 14.15 | 394 | 0.2792 | 32.41 |
| Dingo | 150 | 18 × 3.35 | 1 × 3.35 | 16.75 | 506 | — | — |
| Wolf | 150 | 30 × 2.59 | 7 × 2.59 | 18.13 | 726 | 0.1871 | 67.34 |
| Lynx | 175 | 30 × 2.79 | 7 × 2.79 | 19.53 | 842 | — | — |
| Panther | 200 | 30 × 3.00 | 7 × 3.00 | 21.00 | 974 | 0.1390 | 89.67 |
| Bear | 250 | 30 × 3.35 | 7 × 3.35 | — | 1214 | — | — |
| Goat | 320 | 30 × 3.71 | 7 × 3.71 | — | 1489 | — | — |
| Zebra | 420 (428.9 actual) | 54 × 3.18 | 7 × 3.18 | 28.62 | 1621 | 0.06868 | 130.32 |
| Moose | 520 (528.5 actual) | 54 × 3.53 | 7 × 3.53 | 31.77 | 1998 | 0.05595 | 159.60 |
Where a cell reads “—”, that value is not published on the Part 2 basis in the sources we work from. We confirm it against the printed standard rather than interpolating.
The mistake
IS 398 has more than one part, and Part 2 and Part 5 publish the same codewords with different numbers. Diameters and weights agree. Resistances on the Part 5 basis run around 2–3% lower, and breaking loads around 2–3% higher, consistent with higher-conductivity aluminium and higher-grade steel wire.
Neither set is wrong. Mixing them is. A specification sheet that takes resistance from one part and breaking load from the other is internally inconsistent, and a utility QA engineer checking a submitted GTP against the standard will find it. It is one of the easiest technical errors to spot and one of the most embarrassing to have to explain.
The fix is trivial: put the part number in the table header. “IS 398 (Part 2):1996”, not “as per IS”. Then anyone reading it knows which basis applies, and a comparison against another supplier's figures is like for like.
Nominal against actual area
Two of the transmission conductors are sold under an area they do not actually have. Zebra is quoted as “400” or “420 mm²” but its actual aluminium area is 428.9 mm². Moose is quoted as “520 mm²” against an actual 528.5 mm². Both conventions circulate in the market. Publish both columns and the ambiguity disappears.
Drum lengths and what goes on the drum
Standard drum lengths in Indian utility practice are 2,000 m for Squirrel and Weasel, 1,000 m for Rabbit, Dog and Wolf, all at ±5%; most purchasers now state the drum length on the order. Random lengths are normally accepted at a minimum 80% of standard length, capped at 5–10% of the ordered quantity depending on the utility.
The drum itself should be stencilled with the contract number, consignee, manufacturer, size, length, gross and net weight, barrel diameter at three points, an arrow showing the unwinding direction, and the cable end positions. Missing stencilling is a routine rejection at receipt inspection.
Tolerances worth checking at inspection
- Aluminium wire diameter: ±1% on nominal
- Steel wire diameter: ±2% on nominal
- Steel wire mass: ±5%
- Gross drum weight: ±10%
Acceptance testing is normally on a minimum 10% of drums per lot, covering surface condition, wire diameter, lay ratio, individual wire breaking load, conductor UTS, stress–strain, ductility, wrapping test, DC resistance, and galvanizing mass and uniformity on the steel core.
