{
  "node": {
    "id": "term:arcing",
    "type": "Term",
    "label": "Arcing",
    "properties": {
      "id": "arcing",
      "name": "Arcing",
      "aka": [
        "electric arc",
        "DC arc"
      ],
      "section": "topic-hvsafety",
      "definition": "Current continuing through ionised gas across a gap, typically between contacts as they separate. An AC arc goes out by itself at each current zero, a hundred times a second at 50 Hz; a DC arc has no zero and keeps burning until it is stretched and cooled so far that its voltage exceeds the source’s, which makes high-voltage DC far harder to interrupt.",
      "related": [
        "contactor-arc-suppression",
        "arc-flash",
        "contactor",
        "fuse",
        "direct-current",
        "electrical-breakdown"
      ],
      "url": "https://lemonergy.com/learn/glossary/arcing/",
      "mentions": []
    }
  },
  "edges": [
    {
      "id": "edge:5055",
      "source": "term:arcing",
      "target": "topic:topic-hvsafety",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5056",
      "source": "term:arcing",
      "target": "term:contactor-arc-suppression",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5057",
      "source": "term:arcing",
      "target": "term:arc-flash",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5058",
      "source": "term:arcing",
      "target": "term:contactor",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5059",
      "source": "term:arcing",
      "target": "term:fuse",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5060",
      "source": "term:arcing",
      "target": "term:direct-current",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5061",
      "source": "term:arcing",
      "target": "term:electrical-breakdown",
      "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:contactor-arc-suppression",
      "type": "Term",
      "label": "Contactor arc suppression",
      "properties": {
        "id": "contactor-arc-suppression",
        "name": "Contactor arc suppression",
        "aka": [
          "magnetic blow-out",
          "arc quenching",
          "arc chute",
          "gas-filled contactor"
        ],
        "section": "topic-hvsafety",
        "definition": "The means by which a high-voltage DC contactor breaks current under load. Permanent magnets push the arc sideways to stretch and cool it — so many contactors are polarised and break less current in reverse — and hermetically sealed chambers filled with hydrogen or hydrogen–nitrogen gas cool the arc and keep the contacts clean.",
        "related": [
          "contactor",
          "arcing",
          "contactor-weld-detection",
          "battery-disconnect-unit",
          "pyrofuse"
        ],
        "url": "https://lemonergy.com/learn/glossary/contactor-arc-suppression/",
        "mentions": []
      }
    },
    {
      "id": "term:arc-flash",
      "type": "Term",
      "label": "Arc flash",
      "properties": {
        "id": "arc-flash",
        "name": "Arc flash",
        "aka": [
          "DC arc flash",
          "arc-flash hazard",
          "incident energy"
        ],
        "section": "topic-hvsafety",
        "definition": "The burst of heat, light and pressure released by a fault arc. The hazard to a worker is rated as incident energy at working distance; 1.2 cal/cm² is the usual onset of second-degree burns. Large battery systems can feed fault currents of many kiloamperes, so arc flash sets protective clothing and approach limits under NFPA 70E.",
        "unit": "cal/cm²",
        "related": [
          "arcing",
          "external-short-circuit",
          "stationary-storage",
          "emergency-shutdown",
          "fuse-coordination"
        ],
        "url": "https://lemonergy.com/learn/glossary/arc-flash/",
        "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: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:direct-current",
      "type": "Term",
      "label": "Direct and alternating current",
      "properties": {
        "id": "direct-current",
        "name": "Direct and alternating current",
        "abbr": "DC, AC",
        "section": "topic-units",
        "definition": "A battery stores and delivers direct current, flowing one way; the grid and most motors use alternating current, which reverses many times a second. An inverter converts one into the other, and every conversion loses a few percent.",
        "related": [
          "current",
          "inverter",
          "charger",
          "energy-efficiency"
        ],
        "url": "https://lemonergy.com/learn/glossary/direct-current/",
        "mentions": []
      }
    },
    {
      "id": "term:electrical-breakdown",
      "type": "Term",
      "label": "Electrical breakdown",
      "properties": {
        "id": "electrical-breakdown",
        "name": "Electrical breakdown",
        "aka": [
          "dielectric breakdown",
          "breakdown voltage",
          "dielectric strength"
        ],
        "section": "topic-hvsafety",
        "definition": "The sudden failure of an insulator to block current once the electric field exceeds its dielectric strength, about 3 kV/mm for air at sea level and far higher for solid films. In 800 V drives, partial discharges in voids, driven by fast inverter switching edges, can erode insulation until it fails at normal voltage.",
        "related": [
          "clearance",
          "insulation-resistance",
          "insulation-test",
          "arcing",
          "creepage-distance"
        ],
        "url": "https://lemonergy.com/learn/glossary/electrical-breakdown/",
        "mentions": [
          "inverter"
        ]
      }
    }
  ]
}