{
  "name": "Generator size JSON endpoint",
  "description": "Returns running-watt, startup-surge, altitude-derated output, margin, and recommended generator class from RV appliance and charger overlap assumptions.",
  "publisher": {
    "name": "OffGridRVHub",
    "url": "https://www.offgridrvhub.com"
  },
  "source": {
    "endpoint": "https://www.offgridrvhub.com/tools/api/generator-size.json",
    "fullCalculator": "https://www.offgridrvhub.com/tools/generator-size-calculator",
    "assumptions": "https://www.offgridrvhub.com/tools/calculator-assumptions",
    "documentation": "https://www.offgridrvhub.com/tools/calculator-api"
  },
  "caveat": "This is a planning estimate for RV education and comparison. It is not electrical, plumbing, safety, or installation advice.",
  "input": {
    "loads": [
      {
        "name": "Rooftop AC with soft start",
        "runningWatts": 1350,
        "startupSurgeWatts": 2600,
        "quantity": 1
      },
      {
        "name": "Microwave",
        "runningWatts": 1200,
        "startupSurgeWatts": 1200,
        "quantity": 1
      }
    ],
    "batteryChargerWatts": 900,
    "generatorRatedWatts": 3500,
    "generatorSurgeWatts": 4500,
    "altitudeFeet": 2500,
    "deratePercentPerThousandFeet": 3,
    "planningBufferPercent": 15
  },
  "result": {
    "totalRunningWatts": 3450,
    "largestSurgeDeltaWatts": 1250,
    "estimatedStartupWatts": 4700,
    "bufferedRunningWatts": 3967,
    "bufferedStartupWatts": 5405,
    "altitudeDeratePercent": 7.5,
    "effectiveRatedWatts": 3238,
    "effectiveSurgeWatts": 4163,
    "runningMarginWatts": -729,
    "surgeMarginWatts": -1242,
    "runningLoadPercent": 107,
    "surgeLoadPercent": 113,
    "recommendedRatedWatts": 4500,
    "recommendedSurgeWatts": 6000,
    "recommendedGeneratorLabel": "4,500W running / 6,000W surge target",
    "canRunEnteredLoads": false,
    "tightGenerator": false,
    "surgeDominated": true,
    "verdictTitle": "This generator is undersized for the entered overlap",
    "verdictDetail": "After the 7.5% altitude derate, the entered generator has about 3,238W running and 4,163W surge available. The entered overlap needs about 3,450W running and 4,700W at startup before buffer.",
    "recommendedNextMove": "Move one load out of the overlap, reduce charger watts, add a soft-start device for compressor loads, or shop in the recommended generator class before relying on this setup.",
    "watchOuts": [
      "This is a planning calculator. Final generator selection should follow the generator manual, appliance labels, transfer switch limits, grounding instructions, ventilation requirements, and campground or public-land rules.",
      "Startup math assumes the listed running loads are already on and the single largest startup surge happens next. If two compressors or motors start at the same time, real surge can be higher.",
      "Altitude derating varies by generator model and fuel system. Use the manual's derate table when you have it, then adjust the derate input here.",
      "Startup surge is driving the recommendation. A soft-start device or changing load timing may do more than buying a much larger generator."
    ]
  }
}