{
  "node": {
    "id": "term:overcurrent-protection",
    "type": "Term",
    "label": "Overcurrent protection",
    "properties": {
      "id": "overcurrent-protection",
      "name": "Overcurrent protection",
      "abbr": "OCP",
      "aka": [
        "short-circuit protection",
        "discharge overcurrent",
        "charge overcurrent"
      ],
      "section": "topic-pack",
      "definition": "Opening a pack’s switches when current exceeds a set limit for longer than a set delay. Protection chips use tiers — a moderate overcurrent trips after milliseconds to seconds, a short circuit within microseconds — sensed across a shunt or the MOSFETs’ own on-resistance, with a fuse or PTC device as back-up.",
      "related": [
        "protection-circuit",
        "mosfet",
        "current-sensor",
        "fuse",
        "ptc",
        "short-circuit-test"
      ],
      "url": "https://lemonergy.com/learn/glossary/overcurrent-protection/",
      "mentions": [
        "short-circuit"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:belongsTo/term:overcurrent-protection/topic:topic-pack",
      "source": "term:overcurrent-protection",
      "target": "topic:topic-pack",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:protection-circuit",
      "source": "term:overcurrent-protection",
      "target": "term:protection-circuit",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:mosfet",
      "source": "term:overcurrent-protection",
      "target": "term:mosfet",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:current-sensor",
      "source": "term:overcurrent-protection",
      "target": "term:current-sensor",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:fuse",
      "source": "term:overcurrent-protection",
      "target": "term:fuse",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:ptc",
      "source": "term:overcurrent-protection",
      "target": "term:ptc",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:relatedTo/term:overcurrent-protection/term:short-circuit-test",
      "source": "term:overcurrent-protection",
      "target": "term:short-circuit-test",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/overcurrent-protection/short-circuit",
      "source": "term:overcurrent-protection",
      "target": "term:short-circuit",
      "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-pack",
      "type": "Topic",
      "label": "Modules, packs and battery management",
      "properties": {
        "id": "topic-pack",
        "name": "Modules, packs and battery management",
        "lede": "From a single cell to a working battery system, and the electronics that keep it safe.",
        "context": "Make series/parallel architecture explicit.",
        "example": "Twelve 3.6 V, 5 Ah cells in 6s2p give 21.6 V, 10 Ah and 216 Wh nominally before other restrictions.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/cell-architecture/",
        "lesson_label": "Open cell architecture"
      }
    },
    {
      "id": "term:protection-circuit",
      "type": "Term",
      "label": "Protection circuit module",
      "properties": {
        "id": "protection-circuit",
        "name": "Protection circuit module",
        "abbr": "PCM",
        "aka": [
          "protection board",
          "PCB"
        ],
        "section": "topic-pack",
        "definition": "The small circuit on a consumer cell or pack that disconnects it on overvoltage, undervoltage, overcurrent or overtemperature, using MOSFETs as switches. It is the minimum BMS; it protects but does not estimate state or balance.",
        "related": [
          "bms",
          "overcharge",
          "over-discharge",
          "fuel-gauge",
          "secondary-protection",
          "overcurrent-protection"
        ],
        "url": "https://lemonergy.com/learn/glossary/protection-circuit/",
        "mentions": []
      }
    },
    {
      "id": "term:mosfet",
      "type": "Term",
      "label": "MOSFET",
      "properties": {
        "id": "mosfet",
        "name": "MOSFET",
        "aka": [
          "metal–oxide–semiconductor field-effect transistor",
          "power MOSFET"
        ],
        "section": "topic-data",
        "definition": "A transistor switched by the voltage on its gate, with an on-resistance of milliohms or less in power parts. Low-voltage packs use back-to-back pairs as charge and discharge switches, since each conducts backwards through its body diode; BMS chips use small ones for balancing, and silicon-carbide MOSFETs switch 800 V inverters.",
        "related": [
          "protection-circuit",
          "pulse-width-modulation",
          "cell-balancing",
          "inverter",
          "buck-boost-converter"
        ],
        "url": "https://lemonergy.com/learn/glossary/mosfet/",
        "mentions": [
          "bms"
        ]
      }
    },
    {
      "id": "term:current-sensor",
      "type": "Term",
      "label": "Current sensor",
      "properties": {
        "id": "current-sensor",
        "name": "Current sensor",
        "aka": [
          "shunt",
          "Hall sensor"
        ],
        "section": "topic-pack",
        "definition": "The device that measures pack current for coulomb counting and protection: a precision shunt resistor read by an amplifier, or a Hall-effect sensor around the cable. Offset error in this sensor is what makes SOC drift between OCV corrections.",
        "related": [
          "coulomb-counting",
          "bms",
          "battery-disconnect-unit",
          "state-of-charge"
        ],
        "url": "https://lemonergy.com/learn/glossary/current-sensor/",
        "mentions": [
          "coulomb",
          "open-circuit-voltage"
        ]
      }
    },
    {
      "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:ptc",
      "type": "Term",
      "label": "Positive temperature coefficient device",
      "properties": {
        "id": "ptc",
        "name": "Positive temperature coefficient device",
        "abbr": "PTC",
        "section": "topic-safety",
        "definition": "A polymer element in series with a cell whose resistance jumps when it heats, choking an external short-circuit current. It resets as it cools, unlike a fuse, but adds resistance and does not help against internal faults.",
        "related": [
          "external-short-circuit",
          "fuse",
          "current-interrupt-device"
        ],
        "url": "https://lemonergy.com/learn/glossary/ptc/",
        "mentions": []
      }
    },
    {
      "id": "term:short-circuit-test",
      "type": "Term",
      "label": "External short-circuit test",
      "properties": {
        "id": "short-circuit-test",
        "name": "External short-circuit test",
        "section": "topic-safety",
        "definition": "Connecting a charged cell’s terminals through a resistance of a few milliohms and recording temperature and outcome. The result depends as much on the cell’s own resistance and its protective devices as on its chemistry.",
        "related": [
          "external-short-circuit",
          "abuse-testing",
          "ptc",
          "fuse"
        ],
        "url": "https://lemonergy.com/learn/glossary/short-circuit-test/",
        "mentions": []
      }
    },
    {
      "id": "term:short-circuit",
      "type": "Term",
      "label": "Short circuit",
      "properties": {
        "id": "short-circuit",
        "name": "Short circuit",
        "section": "topic-units",
        "definition": "A connection of negligible resistance between two points that should be separated, so current is limited only by the source. For a battery it may be external, across the terminals, or internal, between the electrodes inside the cell.",
        "related": [
          "external-short-circuit",
          "internal-short-circuit",
          "fuse",
          "ohms-law"
        ],
        "lesson": "fundamentals/cell-anatomy/#short-circuit",
        "url": "https://lemonergy.com/learn/glossary/short-circuit/",
        "mentions": []
      }
    }
  ]
}