{
  "capability_id": "electrical.ev_voltage",
  "tool_id": "ev-to-volts",
  "engine": "ev-voltage",
  "calculation_version": "1.3.0",
  "generated_at": "2026-09-16T22:03:43.702Z",
  "engine_build": "2026-09-13",
  "test_count": 21,
  "passed": 21,
  "failed": 0,
  "tests_summary": {
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      "total": 12,
      "passed": 12
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    "boundary": {
      "total": 5,
      "passed": 5
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    "property": {
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  "internally_reviewed": false,
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    "scope": [
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      "input semantics",
      "assumptions",
      "limitations",
      "sources",
      "tests"
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    "note": "Domain expert review is optional under CVP (CVP-EXP-01). Absence does not block CVP Verified. See Review policy for supplemental domain assurance."
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  "schema_input": "https://www.calculatorx.com/schemas/electrical.ev_voltage.input.json",
  "schema_output": "https://www.calculatorx.com/schemas/electrical.ev_voltage.output.json",
  "assumptions": [
    "Elementary charge e = 1.602176634×10⁻¹⁹ C exactly (SI defining constant; no uncertainty)",
    "Uses the electrostatic energy–potential relation E = qV",
    "Q(e) and Q(C) denote charge magnitude; sign and direction of the potential difference are not modeled"
  ],
  "limitations": [
    "Charge is magnitude only — electron (−e) vs proton (+e) sign is not modeled",
    "Q = 0 when solving for voltage → ZERO_CHARGE (not 0 V)",
    "Uses exact SI e = 1.602176634×10⁻¹⁹ C",
    "Not a pure eV↔V unit conversion; ΔE = qΔV"
  ],
  "boundary_conditions": [
    "eV→V: Q = 0 → ZERO_CHARGE (hard). V = E/Q is undefined, including 0/0",
    "Charge magnitude must be ≥ 0 (VALUE_MUST_BE_NON_NEGATIVE)",
    "Zero energy with Q ≠ 0 → 0 V",
    "V→eV: zero V or Q → 0 eV (product is defined)",
    "Coulomb path uses exact e = 1.602176634×10⁻¹⁹ C"
  ],
  "sources": [
    {
      "title": "BIPM SI Brochure, 9th edition",
      "section": "SI defining constants — elementary charge e = 1.602176634×10⁻¹⁹ C exactly",
      "url": "https://www.bipm.org/en/publications/si-brochure",
      "supports": "Exact SI elementary charge; coulomb-mode scale; 1 eV = e J",
      "kind": "standard",
      "publisher": "BIPM"
    },
    {
      "title": "BIPM SI base unit — ampere",
      "section": "The ampere is defined by taking the fixed numerical value of the elementary charge e",
      "url": "https://www.bipm.org/en/si-base-units/ampere",
      "supports": "e is an SI defining constant with no uncertainty",
      "kind": "standard",
      "publisher": "BIPM"
    },
    {
      "title": "NIST Guide to the SI (SP 811)",
      "section": "Electronvolt as a non-SI energy unit accepted for use with SI",
      "url": "https://www.nist.gov/pml/special-publication-811",
      "supports": "eV is energy; volts remain SI potential; eV ↔ J via e",
      "kind": "reference"
    }
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        "mode": "ev-v-e",
        "direction": "energy_to_voltage",
        "energy_eV": 1,
        "voltage_V": 1,
        "charge_value": 1,
        "charge_unit": "elementary_charge",
        "charge_convention": "magnitude",
        "elementary_charge_C": 1.602176634e-19
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        "charge_unit": "elementary_charge",
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        "elementary_charge_C": 1.602176634e-19
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        "mode": "ev-v-e",
        "direction": "energy_to_voltage",
        "energy_eV": 1000000,
        "voltage_V": 1000000,
        "charge_value": 1,
        "charge_unit": "elementary_charge",
        "charge_convention": "magnitude",
        "elementary_charge_C": 1.602176634e-19
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      "expect": 25,
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        "direction": "voltage_to_energy",
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        "charge_unit": "elementary_charge",
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        "voltage_V": 4.005441585e-19,
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        "charge_unit": "coulomb",
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        "elementary_charge_C": 1.602176634e-19
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      "tol": 1e-28
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        "charge_unit": "elementary_charge",
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        "energy_eV": 0,
        "voltage_V": 0,
        "charge_value": 10,
        "charge_unit": "elementary_charge",
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        "unit": "eV",
        "mode": "v-ev-c",
        "direction": "voltage_to_energy",
        "energy_eV": 1,
        "voltage_V": 1,
        "charge_value": 1.602176634e-19,
        "charge_unit": "coulomb",
        "charge_convention": "magnitude",
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        "charge_value": 10,
        "charge_unit": "elementary_charge",
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