{
  "node": {
    "id": "term:modbus",
    "type": "Term",
    "label": "Modbus",
    "properties": {
      "id": "modbus",
      "name": "Modbus",
      "section": "topic-pack",
      "definition": "A simple industrial register-based protocol, over serial RS-485 or TCP, that stationary storage systems use between battery, inverter and site controller. It is old, open and universally supported, which is why it survives in grid equipment.",
      "related": [
        "can-bus",
        "energy-management-system",
        "stationary-storage",
        "inverter"
      ],
      "url": "https://lemonergy.com/learn/glossary/modbus/",
      "mentions": [
        "power-plant-controller"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:3031",
      "source": "term:modbus",
      "target": "topic:topic-pack",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:3032",
      "source": "term:modbus",
      "target": "term:can-bus",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3033",
      "source": "term:modbus",
      "target": "term:energy-management-system",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3034",
      "source": "term:modbus",
      "target": "term:stationary-storage",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3035",
      "source": "term:modbus",
      "target": "term:inverter",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/modbus/power-plant-controller",
      "source": "term:modbus",
      "target": "term:power-plant-controller",
      "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:can-bus",
      "type": "Term",
      "label": "CAN bus",
      "properties": {
        "id": "can-bus",
        "name": "CAN bus",
        "aka": [
          "Controller Area Network",
          "ISO 11898"
        ],
        "section": "topic-pack",
        "definition": "The serial network over which a BMS talks to the vehicle or inverter: a two-wire differential bus, defined in ISO 11898, carrying short prioritised messages at up to 1 Mbit/s, or faster with CAN FD. Every node hears every message, and a dominant bit wins arbitration without any collision.",
        "related": [
          "can-high-low",
          "can-fd",
          "termination-resistor",
          "bms",
          "lin-bus",
          "fms-interface"
        ],
        "url": "https://lemonergy.com/learn/glossary/can-bus/",
        "mentions": [
          "inverter"
        ]
      }
    },
    {
      "id": "term:energy-management-system",
      "type": "Term",
      "label": "Energy management system",
      "properties": {
        "id": "energy-management-system",
        "name": "Energy management system",
        "abbr": "EMS",
        "section": "topic-pack",
        "definition": "The site-level controller of a storage system that decides when to charge and discharge according to prices, grid signals and the battery’s limits, and dispatches those commands to the BMS and inverters.",
        "related": [
          "bms",
          "inverter",
          "stationary-storage",
          "modbus",
          "energy-arbitrage"
        ],
        "url": "https://lemonergy.com/learn/glossary/energy-management-system/",
        "mentions": []
      }
    },
    {
      "id": "term:stationary-storage",
      "type": "Term",
      "label": "Stationary storage",
      "properties": {
        "id": "stationary-storage",
        "name": "Stationary storage",
        "abbr": "BESS",
        "aka": [
          "battery energy storage system",
          "ESS"
        ],
        "section": "topic-applications",
        "definition": "Batteries installed in a fixed place — a container at a solar farm, a cabinet in a home — to shift energy in time or support the grid. LFP cells dominate because cost per cycle and safety matter more than mass.",
        "related": [
          "lfp",
          "energy-management-system",
          "inverter",
          "energy-arbitrage",
          "long-duration-storage",
          "ul-9540a"
        ],
        "url": "https://lemonergy.com/learn/glossary/stationary-storage/",
        "mentions": []
      }
    },
    {
      "id": "term:inverter",
      "type": "Term",
      "label": "Inverter",
      "properties": {
        "id": "inverter",
        "name": "Inverter",
        "aka": [
          "power conversion system",
          "PCS"
        ],
        "section": "topic-pack",
        "definition": "The power electronics that turn the battery’s DC into AC for a motor or the grid, and back again for charging. In stationary storage it is called the power conversion system and its rating in kW or MW sets the system’s power independently of the battery’s energy.",
        "related": [
          "pre-charge",
          "dc-dc-converter",
          "stationary-storage",
          "energy-management-system",
          "direct-current",
          "iec-62477-1"
        ],
        "url": "https://lemonergy.com/learn/glossary/inverter/",
        "mentions": []
      }
    },
    {
      "id": "term:power-plant-controller",
      "type": "Term",
      "label": "Power plant controller",
      "properties": {
        "id": "power-plant-controller",
        "name": "Power plant controller",
        "abbr": "PPC",
        "aka": [
          "battery plant controller",
          "plant controller",
          "site controller"
        ],
        "section": "topic-data",
        "definition": "The fast closed-loop controller of a grid-connected battery plant that regulates active and reactive power, voltage and frequency response at the point of connection, dispatching setpoints to the inverters. It enforces the grid code, while the energy management system above it decides the schedule.",
        "related": [
          "energy-management-system",
          "inverter",
          "stationary-storage",
          "frequency-regulation",
          "string"
        ],
        "url": "https://lemonergy.com/learn/glossary/power-plant-controller/",
        "mentions": [
          "reactive-power-support"
        ]
      }
    }
  ]
}