{
  "capability_id": "electrical.voltage_drop",
  "tool_id": "voltage-drop",
  "engine": "voltage-drop",
  "calculation_version": "1.5.2",
  "generated_at": "2026-11-10T05:18:41.668Z",
  "engine_build": "2026-09-12",
  "test_count": 38,
  "passed": 38,
  "failed": 0,
  "tests_summary": {
    "golden": {
      "passed": 12,
      "total": 12
    },
    "boundary": {
      "passed": 12,
      "total": 12
    },
    "property": {
      "passed": 14,
      "total": 14
    }
  },
  "engine_tested": true,
  "expert_reviewed": false,
  "internally_reviewed": false,
  "review_kind": null,
  "source_checked": true,
  "reviewed_by": null,
  "reviewer_role": null,
  "last_reviewed": null,
  "expert_review": {
    "status": "optional_not_performed",
    "reviewer": null,
    "scope": [
      "formula",
      "input semantics",
      "assumptions",
      "limitations",
      "sources",
      "tests"
    ],
    "note": "Domain expert review is optional under CVP (CVP-EXP-01). Absence does not block CVP Verified. See Review policy for supplemental domain assurance."
  },
  "internal_review": {
    "status": "not_applicable",
    "reviewer": null
  },
  "page": "https://www.calculatorx.com/calc/wire/voltage-drop",
  "api": "https://www.calculatorx.com/api/v1/calc/voltage-drop",
  "schema_input": "https://www.calculatorx.com/schemas/electrical.voltage_drop.input.json",
  "schema_output": "https://www.calculatorx.com/schemas/electrical.voltage_drop.output.json",
  "assumptions": [
    "Constant resistance; temperature neglected.",
    "AC estimate assumes PF ≈ 1 and neglects conductor reactance.",
    "DC / resistive 1φ uses round-trip path; 3φ assumes balanced line-to-line drop.",
    "V_system for 3φ is line-to-line; V_load = V_system − V_drop on that same basis.",
    "User supplies an appropriate Ω/km for the conductor and conditions.",
    "When u_* are set, first-order GUM sensitivity with independent inputs (no ρ on this page)."
  ],
  "limitations": [
    "Resistance-only estimate — AC reactance neglected; AC modes assume PF ≈ 1",
    "Not a substitute for code-compliant cable sizing or ampacity",
    "3φ V_system is line-to-line; percent_drop and V_load use that same basis",
    "Zero I/length/R → 0 V (valid); negatives → VALUE_MUST_BE_NON_NEGATIVE",
    "mode must be dc or three (INVALID_MODE otherwise); REST/UI default dc if omitted",
    "V_system if set must be > 0 (VALUE_MUST_BE_POSITIVE); omit it to return volts only",
    "Optional u_* use GUM sensitivity only; empty u_* still returns { V_drop, R_one_way, P_loss, … } without uncertainty",
    "Engine tested, source checked, evidence published (L1). Named expert review is a higher assurance tier (L3), not required for engine-tested status. Not a code-compliance certification."
  ],
  "boundary_conditions": [
    "Missing I/length_m/R_ohm_per_km → MISSING_REQUIRED_INPUT",
    "Non-finite inputs → INVALID_NUMBER",
    "Negative I/length/R → VALUE_MUST_BE_NON_NEGATIVE",
    "Unknown mode → INVALID_MODE (only dc|three)",
    "V_system ≤ 0 → VALUE_MUST_BE_POSITIVE",
    "Zero I, length, or R → 0 V and 0 W (valid soft result)",
    "uncertainty_k without any u_* → INVALID_INPUT",
    "uncertainty_k XOR confidence",
    "Not a substitute for code-compliant cable sizing"
  ],
  "sources": [
    {
      "title": "IEC 60364-5-52:2009+AMD1:2024",
      "section": "Clause 525 / Annex G — Voltage drop in consumers' installations",
      "url": "https://webstore.iec.ch/en/publication/103734",
      "supports": "CalculatorX implements a resistance-only / PF≈1 approximation, not the complete impedance-aware Annex G model. DC/1φ ≈ 2·I·R; balanced 3φ ≈ √3·I·R (reactance and PF neglected on this page).",
      "kind": "standard",
      "accessed": "2026-09-10",
      "clause": "525 / Annex G"
    },
    {
      "title": "IEC 60050 — International Electrotechnical Vocabulary",
      "section": "Voltage drop (IEV 151-15-08)",
      "url": "https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=151-15-08",
      "supports": "Voltage between the terminals of a resistive element due to the current through that element",
      "kind": "standard",
      "accessed": "2026-09-05",
      "clause": "IEV 151-15-08"
    },
    {
      "title": "IEC 60050 — International Electrotechnical Vocabulary",
      "section": "Resistance (IEV 131-12-04)",
      "url": "https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-04",
      "supports": "R = u/I; this page’s resistance-only drop uses V ≈ I·R (reactance neglected)",
      "kind": "standard",
      "accessed": "2026-09-05",
      "clause": "IEV 131-12-04"
    },
    {
      "title": "NFPA 70 — National Electrical Code (NEC)",
      "section": "Informational notes on voltage-drop limits for feeders and branch circuits",
      "url": "https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=70",
      "supports": "Design estimate for conductor voltage drop (not a code substitute)",
      "kind": "standard"
    },
    {
      "title": "NIST Guide to the SI (SP 811)",
      "section": "Volt, ampere, ohm, and metre",
      "url": "https://www.nist.gov/pml/special-publication-811",
      "supports": "SI units for the resistance-based drop model",
      "kind": "reference"
    }
  ],
  "methods": [],
  "fingerprint": "sha256:706e4bbf603a233a4f99d57b83a663ff4374263e7271a2bf3db58c58842133d3",
  "tier": "engine_tested",
  "verification": {
    "tests": {
      "passed": 38,
      "total": 38,
      "golden": 12,
      "boundary": 12,
      "property": 14
    },
    "contract_checks": {
      "passed": 8,
      "total": 8
    }
  },
  "evidence_core_generated_at": "2026-09-12T08:31:40.839Z",
  "rendered_at": "2026-11-10T05:18:41.668Z",
  "release_integrity": {
    "status": "verified",
    "scope": "workspace",
    "production_attestation_required": true,
    "calculation_version": "1.5.2",
    "artifacts": {
      "engine": "1.5.2",
      "page": "1.5.2",
      "capability": "1.5.2",
      "evidence": "1.5.2",
      "input_schema": "1.5.2",
      "output_schema": "1.5.2",
      "mcp_contract": "1.5.2"
    },
    "digests": {
      "input_schema_sha256": "3bfb5b8d5c9afbe1a91d8aeecdd27df18b533a1ffd75dd2f33b9b214e8fdd429",
      "output_schema_sha256": "4f13f3ba3869b287cbb38a6c062ea47c40fbd60156baf76d993ec648fb392075",
      "evidence_sha256": "c859fc50d87f33b26a58f1533e8337e0adaea32a9a712b8019fc67257b5b9b0f",
      "evidence_core_sha256": "c859fc50d87f33b26a58f1533e8337e0adaea32a9a712b8019fc67257b5b9b0f",
      "capability_sha256": "4e3609124e99adac2132b325853eb2190cb4e06918576e019bdc47a74e3c659c",
      "engine_sha256": "c6ebd8436f08b413e1ac6317b2d48550f2e6639a90dff254244e3aa562158b8d",
      "mcp_contract_sha256": "eb3e39ad4a95ed263415b4932f185d5edfe00a2403267b7c5ed5f718d1ff6da3"
    },
    "contract_checks": {
      "total": 8,
      "passed": 8,
      "failed": 0,
      "items": [
        {
          "id": "release-artifacts-aligned",
          "status": "pass",
          "detail": "1.5.2"
        },
        {
          "id": "schema-output-required-declared",
          "status": "pass"
        },
        {
          "id": "schema-valid-input-executes",
          "status": "pass"
        },
        {
          "id": "engine-success-output-validates-schema",
          "status": "pass"
        },
        {
          "id": "schema-rejects-incomplete-input",
          "status": "pass"
        },
        {
          "id": "schema-coverage-requires-u",
          "status": "pass"
        },
        {
          "id": "schema-rejects-boundary-unc-k-without-u",
          "status": "pass"
        },
        {
          "id": "rest-success-payload-validates-schema",
          "status": "pass"
        }
      ]
    },
    "report": "https://www.calculatorx.com/.well-known/calculatorx-release-integrity.json"
  },
  "tests": [],
  "disclosure": {
    "policy": "calculatorx-public-evidence-v1",
    "full_validation": "private",
    "representation": "summary"
  }
}