{
  "node": {
    "id": "term:pyrofuse",
    "type": "Term",
    "label": "Pyrofuse",
    "properties": {
      "id": "pyrofuse",
      "name": "Pyrofuse",
      "aka": [
        "pyrotechnic disconnect"
      ],
      "section": "topic-hvsafety",
      "definition": "A high-voltage disconnect fired by a small pyrotechnic charge on command, typically from the airbag controller in a crash. It cuts the pack from the vehicle in milliseconds, faster and more reliably than a contactor can open under fault current.",
      "related": [
        "fuse",
        "contactor",
        "battery-disconnect-unit",
        "high-voltage-interlock"
      ],
      "url": "https://lemonergy.com/learn/glossary/pyrofuse/",
      "mentions": []
    }
  },
  "edges": [
    {
      "id": "edge:1701",
      "source": "term:pyrofuse",
      "target": "topic:topic-hvsafety",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:1702",
      "source": "term:pyrofuse",
      "target": "term:fuse",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1703",
      "source": "term:pyrofuse",
      "target": "term:contactor",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1704",
      "source": "term:pyrofuse",
      "target": "term:battery-disconnect-unit",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1705",
      "source": "term:pyrofuse",
      "target": "term:high-voltage-interlock",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; 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:fuse",
      "type": "Term",
      "label": "Fuse",
      "properties": {
        "id": "fuse",
        "name": "Fuse",
        "section": "topic-hvsafety",
        "definition": "A link that melts and opens the circuit when current exceeds its rating. Packs use a main fuse in the high-voltage path and often a small fuse on each parallel cell connection, so one shorted cell does not drain its neighbours into the fault.",
        "related": [
          "external-short-circuit",
          "pyrofuse",
          "battery-disconnect-unit",
          "series-parallel",
          "cell-level-fuse"
        ],
        "url": "https://lemonergy.com/learn/glossary/fuse/",
        "mentions": []
      }
    },
    {
      "id": "term:contactor",
      "type": "Term",
      "label": "Contactor",
      "properties": {
        "id": "contactor",
        "name": "Contactor",
        "section": "topic-hvsafety",
        "definition": "A heavy-duty electrically operated switch that connects the pack to the vehicle or inverter and opens it on fault or shutdown. Packs use at least two, one per pole, plus a pre-charge path to avoid welding them on the first connection.",
        "related": [
          "pre-charge",
          "battery-disconnect-unit",
          "pyrofuse",
          "bms"
        ],
        "url": "https://lemonergy.com/learn/glossary/contactor/",
        "mentions": [
          "inverter"
        ]
      }
    },
    {
      "id": "term:battery-disconnect-unit",
      "type": "Term",
      "label": "Battery disconnect unit",
      "properties": {
        "id": "battery-disconnect-unit",
        "name": "Battery disconnect unit",
        "abbr": "BDU",
        "aka": [
          "battery junction box"
        ],
        "section": "topic-hvsafety",
        "definition": "The box inside the pack that holds the contactors, pre-charge circuit, main fuse or pyrofuse and current sensor, where the pack’s high-voltage connections are made and broken.",
        "related": [
          "contactor",
          "pre-charge",
          "fuse",
          "pyrofuse",
          "current-sensor"
        ],
        "url": "https://lemonergy.com/learn/glossary/battery-disconnect-unit/",
        "mentions": []
      }
    },
    {
      "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"
        ]
      }
    }
  ]
}