{
  "starting": {
    "resultSchema": "infrastructure-screen-1",
    "contentVersion": "2.0.0",
    "modelVersion": "1.0.0",
    "lessonId": "transformer-fault-boundaries",
    "model": "transformerScreen",
    "inputs": {
      "mva": 2,
      "voltageV": 400,
      "zPercent": 6,
      "sourceMVA": 250
    },
    "outputs": {
      "fullLoadA": 2886.751345948129,
      "baseOhm": 0.08,
      "transformerOhm": 0.0048,
      "sourceOhm": 0.00064,
      "faultKA": 42.45222567570779
    },
    "inputUnits": {
      "mva": "MVA",
      "voltageV": "V line-to-line",
      "zPercent": "%",
      "sourceMVA": "MVA or null"
    },
    "outputUnits": {
      "fullLoadA": "A",
      "baseOhm": "Ω",
      "transformerOhm": "Ω",
      "sourceOhm": "Ω",
      "faultKA": "kA"
    },
    "assumptions": [
      "The fault screen uses a simplified series impedance equivalent and balanced three-phase current.",
      "Build the two-megavolt-ampere example: At 2 MVA, 400 V and 6% impedance, full-load current is 2,886.75 A, base impedance is 0.08 Ω and transformer impedance is 0.0048 Ω. With an infinite source, the simplified three-phase fault is about 48.11 kA. Adding an illustrative 250 MVA source strength contributes 0.00064 Ω and reduces the screen to about 42.45 kA. Both calculations omit the actual cable route and equipment tolerances."
    ],
    "limitations": [
      "Educational screen only; no equipment selection, facility calibration, professional review or certification.",
      "No dynamics, protection coordination, site conditions or manufacturer-specific behavior are inferred.",
      "Purely reactive, bolted three-phase model; voltage factor is 1.",
      "No zero-sequence, motor, cable, tolerance, protection-setting or breaker-selection result."
    ],
    "sourceLocators": [
      {
        "id": "DCIE-R1",
        "chapter": 3,
        "pdfPages": [
          18,
          21
        ],
        "evidenceStatus": "manuscript-derived; not independent source verification"
      }
    ],
    "inputHash": "7582436480fbbde17a3d23744a53379addd51393630dc2debdd5d97d7fd69605",
    "sourceRevision": "e4d47bd6616aa54e19c7da5ee4e2a98afe6209c1",
    "independentEngineeringVerification": false,
    "resultHash": "536ce6710c517b94a5e227da373ed6277fae83cf8b61ad8f0637d261ae334096"
  },
  "challenge": {
    "resultSchema": "infrastructure-screen-1",
    "contentVersion": "2.0.0",
    "modelVersion": "1.0.0",
    "lessonId": "transformer-fault-boundaries",
    "model": "transformerScreen",
    "inputs": {
      "mva": 2,
      "voltageV": 400,
      "zPercent": 6,
      "sourceMVA": null
    },
    "outputs": {
      "fullLoadA": 2886.751345948129,
      "baseOhm": 0.08,
      "transformerOhm": 0.0048,
      "sourceOhm": 0,
      "faultKA": 48.112522432468815
    },
    "inputUnits": {
      "mva": "MVA",
      "voltageV": "V line-to-line",
      "zPercent": "%",
      "sourceMVA": "MVA or null"
    },
    "outputUnits": {
      "fullLoadA": "A",
      "baseOhm": "Ω",
      "transformerOhm": "Ω",
      "sourceOhm": "Ω",
      "faultKA": "kA"
    },
    "assumptions": [
      "The fault screen uses a simplified series impedance equivalent and balanced three-phase current.",
      "Build the two-megavolt-ampere example: At 2 MVA, 400 V and 6% impedance, full-load current is 2,886.75 A, base impedance is 0.08 Ω and transformer impedance is 0.0048 Ω. With an infinite source, the simplified three-phase fault is about 48.11 kA. Adding an illustrative 250 MVA source strength contributes 0.00064 Ω and reduces the screen to about 42.45 kA. Both calculations omit the actual cable route and equipment tolerances."
    ],
    "limitations": [
      "Educational screen only; no equipment selection, facility calibration, professional review or certification.",
      "No dynamics, protection coordination, site conditions or manufacturer-specific behavior are inferred.",
      "Purely reactive, bolted three-phase model; voltage factor is 1.",
      "No zero-sequence, motor, cable, tolerance, protection-setting or breaker-selection result."
    ],
    "sourceLocators": [
      {
        "id": "DCIE-R1",
        "chapter": 3,
        "pdfPages": [
          18,
          21
        ],
        "evidenceStatus": "manuscript-derived; not independent source verification"
      }
    ],
    "inputHash": "c0eaf6e8d1d4778d9d911bebd839d57787e67de341edf9cedc727db56abcdd95",
    "sourceRevision": "e4d47bd6616aa54e19c7da5ee4e2a98afe6209c1",
    "independentEngineeringVerification": false,
    "resultHash": "429564fb8b58f370ab19ed54e4016cba6b1b6fb11740fd18c3691de1702e78f0"
  },
  "fuel": null,
  "engineeringDecision": "HOLD"
}