{
  "node": {
    "id": "term:insulation-resistance",
    "type": "Term",
    "label": "Insulation resistance",
    "properties": {
      "id": "insulation-resistance",
      "name": "Insulation resistance",
      "aka": [
        "isolation resistance",
        "IMD"
      ],
      "section": "topic-hvsafety",
      "definition": "The resistance between the high-voltage circuit and the vehicle chassis, which must stay above about 100 Ω per volt of pack voltage so a person touching the chassis is safe. An insulation monitoring device measures it continuously.",
      "unit": "Ω/V",
      "related": [
        "pack-voltage",
        "high-voltage-interlock",
        "functional-safety",
        "insulation-test"
      ],
      "url": "https://lemonergy.com/learn/glossary/insulation-resistance/",
      "mentions": [
        "volt"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:2911",
      "source": "term:insulation-resistance",
      "target": "topic:topic-hvsafety",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:2912",
      "source": "term:insulation-resistance",
      "target": "term:pack-voltage",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2913",
      "source": "term:insulation-resistance",
      "target": "term:high-voltage-interlock",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2914",
      "source": "term:insulation-resistance",
      "target": "term:functional-safety",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:2915",
      "source": "term:insulation-resistance",
      "target": "term:insulation-test",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/insulation-resistance/volt",
      "source": "term:insulation-resistance",
      "target": "term:volt",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-hvsafety",
      "type": "Topic",
      "label": "High-voltage and functional safety",
      "properties": {
        "id": "topic-hvsafety",
        "name": "High-voltage and functional safety",
        "lede": "Keeping people safe from the pack’s voltage and keeping its electronics safe when they fail: insulation, switching, fusing and the functional-safety process.",
        "context": "Relate protection to faults, detection and response.",
        "example": "Normal-operation current limits do not demonstrate correct contactor behavior under a welded-contact or sensor fault.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "id": "term:pack-voltage",
      "type": "Term",
      "label": "Pack voltage",
      "properties": {
        "id": "pack-voltage",
        "name": "Pack voltage",
        "aka": [
          "400 V system",
          "800 V system"
        ],
        "section": "topic-pack",
        "definition": "The nominal voltage of the full series string, about 400 V in most electric cars and 800 V in newer ones. Doubling the voltage halves the current for the same power, so cables, connectors and losses shrink and charging can be faster.",
        "unit": "V",
        "related": [
          "series-parallel",
          "dc-fast-charging",
          "high-voltage-interlock",
          "insulation-resistance"
        ],
        "url": "https://lemonergy.com/learn/glossary/pack-voltage/",
        "mentions": [
          "nominal-voltage",
          "string"
        ]
      }
    },
    {
      "id": "term:high-voltage-interlock",
      "type": "Term",
      "label": "High-voltage interlock loop",
      "properties": {
        "id": "high-voltage-interlock",
        "name": "High-voltage interlock loop",
        "abbr": "HVIL",
        "section": "topic-hvsafety",
        "definition": "A low-voltage signal loop threaded through every high-voltage connector and cover. Opening any of them breaks the loop and the BMS drops the contactors, so a technician cannot reach a live conductor.",
        "related": [
          "contactor",
          "pack-voltage",
          "insulation-resistance",
          "functional-safety"
        ],
        "url": "https://lemonergy.com/learn/glossary/high-voltage-interlock/",
        "mentions": [
          "bms"
        ]
      }
    },
    {
      "id": "term:functional-safety",
      "type": "Term",
      "label": "Functional safety",
      "properties": {
        "id": "functional-safety",
        "name": "Functional safety",
        "abbr": "ISO 26262",
        "aka": [
          "ASIL"
        ],
        "section": "topic-hvsafety",
        "definition": "The discipline, standardised for vehicles in ISO 26262, of making sure electronic failures do not cause harm. Battery functions such as overvoltage protection are classified by risk into ASIL levels A to D, which set how redundant and verified their hardware and software must be.",
        "related": [
          "bms",
          "high-voltage-interlock",
          "insulation-resistance",
          "fmea",
          "mcu",
          "iso-13849"
        ],
        "url": "https://lemonergy.com/learn/glossary/functional-safety/",
        "mentions": []
      }
    },
    {
      "id": "term:insulation-test",
      "type": "Term",
      "label": "Insulation resistance test",
      "properties": {
        "id": "insulation-test",
        "name": "Insulation resistance test",
        "aka": [
          "hipot test",
          "dielectric strength test"
        ],
        "section": "topic-testing",
        "definition": "Applying a high DC or AC voltage between the high-voltage circuit and the chassis or housing to verify that insulation holds, with the leakage current below a limit. It is done on every pack at end of line and after abuse tests in R100.",
        "related": [
          "insulation-resistance",
          "un-r100-part-2",
          "high-voltage-interlock",
          "end-of-line-testing"
        ],
        "url": "https://lemonergy.com/learn/glossary/insulation-test/",
        "mentions": [
          "un-r100"
        ]
      }
    },
    {
      "id": "term:volt",
      "type": "Term",
      "label": "Volt",
      "properties": {
        "id": "volt",
        "name": "Volt",
        "abbr": "V",
        "section": "topic-units",
        "definition": "The SI unit of electric potential difference: one joule of energy per coulomb of charge. A lithium-ion cell sits around 3–4 V; packs reach hundreds of volts by putting cells in series.",
        "unit": "V",
        "related": [
          "voltage",
          "nominal-voltage",
          "series-parallel"
        ],
        "url": "https://lemonergy.com/learn/glossary/volt/",
        "mentions": [
          "coulomb",
          "joule"
        ]
      }
    }
  ]
}