{
  "node": {
    "id": "term:fault-injection-testing",
    "type": "Term",
    "label": "Fault injection testing",
    "properties": {
      "id": "fault-injection-testing",
      "name": "Fault injection testing",
      "aka": [
        "fault insertion test",
        "fault injection"
      ],
      "section": "topic-testing",
      "definition": "Deliberately introducing faults — a broken sense wire, a stuck temperature reading, a welded contactor, a lost CAN message — into a BMS or pack to prove each is detected and brought to a safe state in time. Functional-safety standards such as ISO 26262 expect it, and HIL rigs make it safe and repeatable.",
      "related": [
        "functional-safety",
        "hil",
        "bms",
        "fmea",
        "battery-emulator",
        "dtc"
      ],
      "url": "https://lemonergy.com/learn/glossary/fault-injection-testing/",
      "mentions": [
        "contactor",
        "contactor-weld-detection"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:5483",
      "source": "term:fault-injection-testing",
      "target": "topic:topic-testing",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5484",
      "source": "term:fault-injection-testing",
      "target": "term:functional-safety",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5485",
      "source": "term:fault-injection-testing",
      "target": "term:hil",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5486",
      "source": "term:fault-injection-testing",
      "target": "term:bms",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5487",
      "source": "term:fault-injection-testing",
      "target": "term:fmea",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5488",
      "source": "term:fault-injection-testing",
      "target": "term:battery-emulator",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5489",
      "source": "term:fault-injection-testing",
      "target": "term:dtc",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/fault-injection-testing/contactor",
      "source": "term:fault-injection-testing",
      "target": "term:contactor",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/fault-injection-testing/contactor-weld-detection",
      "source": "term:fault-injection-testing",
      "target": "term:contactor-weld-detection",
      "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-testing",
      "type": "Topic",
      "label": "Testing methods",
      "properties": {
        "id": "topic-testing",
        "name": "Testing methods",
        "lede": "The measurements and test procedures that characterise a cell or pack, from capacity and pulse tests to abuse and environmental tests.",
        "context": "Record specimen, state, instrument, temperature and timing.",
        "example": "Resistance immediately after a current step can differ from a ten-second value because slower polarization contributes.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/",
        "lesson_label": "Open capacity measurements"
      }
    },
    {
      "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:hil",
      "type": "Term",
      "label": "Hardware-in-the-loop",
      "properties": {
        "id": "hil",
        "name": "Hardware-in-the-loop",
        "abbr": "HIL",
        "aka": [
          "SIL",
          "MIL",
          "software-in-the-loop",
          "model-in-the-loop"
        ],
        "section": "topic-data",
        "definition": "Testing a real BMS controller against a real-time simulation of the battery, vehicle and charger, so faults that would be dangerous on real cells can be injected safely. It follows model-in-the-loop and software-in-the-loop, where the same logic is tested as a model or as code on a PC.",
        "related": [
          "battery-emulator",
          "fpga",
          "bmu",
          "functional-safety",
          "equivalent-circuit-model",
          "fault-injection-testing"
        ],
        "url": "https://lemonergy.com/learn/glossary/hil/",
        "mentions": [
          "charger",
          "bms"
        ]
      }
    },
    {
      "id": "term:bms",
      "type": "Term",
      "label": "Battery management system",
      "properties": {
        "id": "bms",
        "name": "Battery management system",
        "abbr": "BMS",
        "section": "topic-pack",
        "definition": "The electronics and software that keep a battery inside its safe window: measuring every cell voltage and many temperatures, estimating SOC and SOH, balancing cells, computing current limits, controlling the contactors and reporting over the vehicle network.",
        "related": [
          "state-of-charge",
          "cell-balancing",
          "state-of-power",
          "cell-supervision-circuit",
          "contactor",
          "can-bus"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/bms/",
        "mentions": [
          "state-of-health",
          "cell-voltage"
        ]
      }
    },
    {
      "id": "term:fmea",
      "type": "Term",
      "label": "Failure mode and effects analysis",
      "properties": {
        "id": "fmea",
        "name": "Failure mode and effects analysis",
        "abbr": "FMEA",
        "section": "topic-hvsafety",
        "definition": "A structured review that lists every way a component or process could fail, its effect, and how likely it is to happen and be detected, scoring each to prioritise fixes. Battery programmes run it on the cell, the pack design and the production process.",
        "related": [
          "functional-safety",
          "abuse-testing",
          "cell-design",
          "fault-tree-analysis"
        ],
        "url": "https://lemonergy.com/learn/glossary/fmea/",
        "mentions": []
      }
    },
    {
      "id": "term:battery-emulator",
      "type": "Term",
      "label": "Battery and cell emulator",
      "properties": {
        "id": "battery-emulator",
        "name": "Battery and cell emulator",
        "section": "topic-data",
        "definition": "A programmable power source that behaves like a battery or like each cell of a string, so a BMS or charger can be tested at any voltage, state of charge or fault without real cells. Cell emulators drive every AFE input separately.",
        "related": [
          "hil",
          "afe",
          "fpga",
          "cycler"
        ],
        "url": "https://lemonergy.com/learn/glossary/battery-emulator/",
        "mentions": [
          "charger",
          "state-of-charge",
          "bms"
        ]
      }
    },
    {
      "id": "term:dtc",
      "type": "Term",
      "label": "Diagnostic trouble code",
      "properties": {
        "id": "dtc",
        "name": "Diagnostic trouble code",
        "abbr": "DTC",
        "aka": [
          "fault code"
        ],
        "section": "topic-data",
        "definition": "A coded fault a controller stores when a check fails — a cell overvoltage, a sensor out of range, an isolation fault — with a status and often a snapshot of conditions when it occurred. Reading and interpreting DTCs is the first step of any battery root-cause analysis.",
        "related": [
          "uds",
          "bmu",
          "insulation-resistance",
          "freeze-frame"
        ],
        "url": "https://lemonergy.com/learn/glossary/dtc/",
        "mentions": [
          "insulation-fault"
        ]
      }
    },
    {
      "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:contactor-weld-detection",
      "type": "Term",
      "label": "Contactor weld detection",
      "properties": {
        "id": "contactor-weld-detection",
        "name": "Contactor weld detection",
        "aka": [
          "welded contactor",
          "stuck contactor diagnostic",
          "contactor diagnostics"
        ],
        "section": "topic-hvsafety",
        "definition": "A diagnostic that checks a contactor really opened when told to. The BMS compares voltages on each side of each contactor — if the load side still shows pack voltage after opening, the contacts have welded — or reads mirror auxiliary contacts. A welded contactor is latched as a fault, because the pack can no longer be fully disconnected.",
        "related": [
          "contactor",
          "pre-charge",
          "battery-disconnect-unit",
          "dtc",
          "contactor-arc-suppression"
        ],
        "url": "https://lemonergy.com/learn/glossary/contactor-weld-detection/",
        "mentions": [
          "pack-voltage",
          "bms"
        ]
      }
    }
  ]
}