{
  "schemaVersion": "1.0",
  "id": "https://elect-learn.org/zh/lesson/06-series-parallel-voltage-drop/",
  "url": "https://elect-learn.org/zh/lesson/06-series-parallel-voltage-drop/",
  "markdownUrl": "https://elect-learn.org/zh/lesson/06-series-parallel-voltage-drop/index.md",
  "jsonUrl": "https://elect-learn.org/zh/lesson/06-series-parallel-voltage-drop/index.json",
  "language": "zh",
  "title": "串联、并联、负载与压降",
  "description": "理解住宅回路为什么通常并联，压降和连接松动为什么会让设备异常。",
  "kind": "lesson",
  "safetyNotice": "学习参考：不同国家/地区的电气规范、许可和验收主体差异很大，本课程不替代当地法规、持证培训、现场许可或主管部门要求。任何实操前都应断电、验电，并遵守当地 AHJ/监管机构和雇主流程。",
  "sections": [
    {
      "id": "series-load",
      "heading": "Series load（串联负载）是什么意思？",
      "paragraphs": [
        "串联负载是与其他元件处于同一条电流通路中的负载。在理想串联回路中，各元件电流相同，电源电压分配在各元件两端；并联支路连接于相同的两个节点，在理想模型中电压相同。"
      ],
      "question": "两个 10 Ω 电阻串联于理想 12 V 电源两端。回路电流是多少？每个电阻两端电压是多少？",
      "answer": "总电阻 20 Ω，因此 I = 12 / 20 = 0.6 A。每个电阻两端电压为 0.6 × 10 = 6 V。这是纸面计算，不是器件选型或接线指导。",
      "links": [
        {
          "title": "电气符号图解与读图练习",
          "url": "https://elect-learn.org/zh/guides/electrical-drawing-symbols/"
        },
        {
          "title": "核对理想欧姆定律计算",
          "url": "https://elect-learn.org/zh/tools/ohms-law-calculator/"
        }
      ]
    },
    {
      "id": "section-1",
      "heading": "课程信息",
      "paragraphs": [
        "电路基础 · 基础 · 20 min",
        "负载"
      ]
    },
    {
      "id": "section-2",
      "heading": "负载相同，换一种接法会怎样？",
      "paragraphs": [
        "相同电源、相同电阻，只改变连接方式，就能比较总电流与每个负载的电压。"
      ],
      "items": [
        "串联只有一条路，各元件电流相同。",
        "理想并联各支路电压相同，总电流为支路之和。",
        "实际导线有电阻；压降随电流与线路电阻增大。"
      ]
    },
    {
      "id": "section-3",
      "heading": "学习目标",
      "items": [
        "区分串联和并联负载行为。",
        "理解压降与导线长度、电流和连接质量有关。",
        "把发热和松动连接联系起来。"
      ]
    },
    {
      "id": "section-4",
      "heading": "远端工具启动时灯变暗",
      "paragraphs": [
        "车库远端插座接电锯，启动瞬间灯明显变暗。",
        "错误判断: 认为只要能转起来就没问题。",
        "停手边界: 出现持续发热、焦味、火花或反复跳闸时停止使用。",
        "推理路径: 检查负载电流、导线长度、连接点、回路容量和是否需要专用回路。",
        "复习: 常考：并联回路、压降、连接电阻和过载。"
      ]
    },
    {
      "id": "section-5",
      "heading": "完整知识点",
      "items": [
        "并联让每个负载获得近似完整电源电压。",
        "导线也有电阻，大电流和长距离会带来更明显压降。",
        "松动连接像额外电阻，会发热并造成间歇性故障。"
      ]
    },
    {
      "id": "tool-multimeter",
      "heading": "数字万用表",
      "paragraphs": [
        "测量电压、连续性和电阻，用来验证现象而不是猜测。",
        "误用与边界: 把表笔插错孔或量程选错，可能烧表或造成危险。"
      ]
    },
    {
      "id": "tool-wire-nut",
      "heading": "压线帽",
      "paragraphs": [
        "把合适数量和规格的导线机械连接并绝缘。",
        "误用与边界: 规格不匹配、铜线未齐或未拉拽检查，都会造成松动。"
      ]
    },
    {
      "id": "tool-cable",
      "heading": "NM 线缆/导线",
      "paragraphs": [
        "承载回路电流，颜色和标识帮助识别用途。",
        "误用与边界: 线规、护套、环境或颜色使用错误都可能违反规范。"
      ]
    },
    {
      "id": "section-9",
      "heading": "常见误区",
      "items": [
        "把灯变暗都归因于灯泡质量。",
        "忽略接线端子松动或压线帽不良。",
        "把延长线当长期固定布线。"
      ]
    },
    {
      "id": "section-10",
      "heading": "安全流程",
      "items": [
        "记录故障是否只在大负载启动时出现。",
        "断电后检查可见连接点是否变色、松动或发热痕迹。",
        "需要改线或增设回路时交由持证人员并按许可流程。"
      ],
      "ordered": true
    },
    {
      "id": "quiz-1",
      "heading": "住宅插座通常串联还是并联供电？",
      "paragraphs": [
        "并联，这样每个负载获得近似完整电源电压。"
      ]
    },
    {
      "id": "quiz-2",
      "heading": "松动连接为什么危险？",
      "paragraphs": [
        "它增加接触电阻，可能发热、打火并造成间歇性故障。"
      ]
    },
    {
      "id": "section-13",
      "heading": "回头看",
      "links": [
        {
          "title": "复习第 4 课：电流越大，发热风险越高。",
          "url": "https://elect-learn.org/zh/lesson/04-voltage-current-power/"
        },
        {
          "title": "复习第 5 课：工作电流路径走火线和中性线。",
          "url": "https://elect-learn.org/zh/lesson/05-hot-neutral-ground/"
        }
      ]
    }
  ],
  "dateModified": "2026-10-23",
  "publisher": {
    "name": "Elect Learn",
    "url": "https://elect-learn.org"
  },
  "review": {
    "status": "not-independently-reviewed",
    "statement": "尚无独立专业审校记录。参考来源不代表来源机构审校或认可本站。",
    "policyUrl": "https://elect-learn.org/zh/methodology/"
  }
}