Wire Gauge (AWG/SWG) ↔ Diameter/Area Converter implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t7-060

Effect

Computation or source lookup only

Input and validation requirements

The specification does not define rejection behavior for zero diameter, does not identify the exact valid AWG range, and does not require an explicit AWG-versus-SWG selector or diameter unit. These omissions permit undefined outputs and materially different numeric results.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "standard": "AWG",
    "gauge": 36,
    "material": "annealed copper",
    "temperature_C": 20,
    "requested_resistance_lengths": [
      "1 km",
      "1000 ft"
    ]
  },
  "expected_outputs": {
    "diameter_mm": 0.127,
    "area_mm2": 0.012667687,
    "resistance_ohm_per_km": 1326.21,
    "resistance_ohm_per_1000ft": 404.23
  },
  "reference_data": {
    "awg_row": {
      "gauge": 36,
      "diameter_mm": 0.127,
      "source_convention": "AWG standard, widely tabulated standard value"
    },
    "copper_resistivity_ohm_m_20C": 1.68e-8,
    "source_convention_resistivity": "widely tabulated standard value for copper at 20 °C",
    "pi": 3.141592653589793,
    "source_convention_pi": "mathematical constant",
    "metres_per_1000ft": 304.8,
    "source_convention_length": "exact SI/international-foot conversion"
  },
  "working": "d=0.127 mm (the exact AWG-36 table entry). A=πd²/4=3.141592653589793×(0.127²)/4=3.141592653589793×0.016129/4=0.012667687 mm². Convert area: A=0.012667687×10^-6=1.2667687×10^-8 m². R/km=ρL/A=(1.68×10^-8 Ω·m×1000 m)/(1.2667687×10^-8 m²)=1326.21 Ω/km. R/1000 ft=(1.68×10^-8×304.8)/(1.2667687×10^-8)=404.23 Ω/1000 ft."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche7/tranche7-results.json