{
 "schema": "spawner-tool/v1",
 "id": "bot_021",
 "name": "PV-String Leerlaufspannung Voc Messprotokoll Rechner DIN EN 62446",
 "description": "Berechnen Sie die erwartete und maximale Leerlaufspannung einer PV‑String und prüfen Sie die Messabweichung nach DIN EN 62446 (VDE 0126‑23‑1) für die Inbetriebnahme.",
 "url": "https://fachrechner.com/de/pv-string-leerlaufspannung-voc-messprotokoll/",
 "spec_url": "https://fachrechner.com/de/pv-string-leerlaufspannung-voc-messprotokoll/spec.json",
 "language": "de",
 "market": "CH",
 "live_since": null,
 "inputs": [
  {
   "id": "n_module",
   "label": "Anzahl Module im String N",
   "unit": "-",
   "min": 1.0,
   "max": 40.0,
   "step": 1.0,
   "default": 18.0
  },
  {
   "id": "uoc_stc",
   "label": "Leerlaufspannung Modul bei STC U_oc,STC (Datenblatt)",
   "unit": "V",
   "min": 5.0,
   "max": 100.0,
   "step": 0.01,
   "default": 49.5
  },
  {
   "id": "beta_uoc",
   "label": "Temperaturkoeffizient der Leerlaufspannung β_Uoc (Datenblatt, negativ)",
   "unit": "%/K",
   "min": -0.5,
   "max": -0.1,
   "step": 0.01,
   "default": -0.28
  },
  {
   "id": "t_mess",
   "label": "Modultemperatur bei der Messung T_mess (Rückseite, Oberflächenfühler)",
   "unit": "°C",
   "min": -20.0,
   "max": 85.0,
   "step": 0.5,
   "default": 35.0
  },
  {
   "id": "t_min",
   "label": "Minimale Auslegungstemperatur T_min (Standort, Winter)",
   "unit": "°C",
   "min": -30.0,
   "max": 10.0,
   "step": 1.0,
   "default": -10.0
  },
  {
   "id": "uoc_mess",
   "label": "Gemessene Leerlaufspannung des Strings U_oc,mess (Messgerät)",
   "unit": "V",
   "min": 0.0,
   "max": 1500.0,
   "step": 0.1,
   "default": 860.0
  }
 ],
 "constants": [],
 "outputs": [
  {
   "id": "uoc_soll",
   "label": "Erwartete String‑Leerlaufspannung bei Messtemperatur",
   "unit": "V",
   "decimals": 2,
   "expression": "n_module * uoc_stc * (1 + (beta_uoc / 100) * (t_mess - 25))"
  },
  {
   "id": "uoc_max",
   "label": "Maximale String‑Leerlaufspannung bei T_min",
   "unit": "V",
   "decimals": 2,
   "expression": "n_module * uoc_stc * (1 + (beta_uoc / 100) * (t_min - 25))"
  },
  {
   "id": "abweichung",
   "label": "Abweichung Messung zu Sollwert",
   "unit": "%",
   "decimals": 2,
   "expression": "abs(uoc_mess - uoc_soll) / uoc_soll * 100"
  }
 ],
 "formula": "U_oc,soll = N·U_oc,STC·[1+β_Uoc/100·(T_mess‑25)] U_oc,max = N·U_oc,STC·[1+β_Uoc/100·(T_min‑25)] Abweichung % = |U_oc,mess‑U_oc,soll| / U_oc,soll·100",
 "expression_language": {
  "name": "safeexpr",
  "syntax": "Python arithmetic subset: + - * / ** %, parentheses, numbers, input/constant ids and ids of earlier outputs, functions abs sqrt log log10 exp floor ceil sin cos tan min max round(x,n), constants pi e, conditionals (a if x > y else b)",
  "semantics": "% is fmod; round() rounds half away from zero; outputs are evaluated in the listed order"
 },
 "example": {
  "inputs": {
   "n_module": 18.0,
   "uoc_stc": 49.5,
   "beta_uoc": -0.28,
   "t_mess": 35.0,
   "t_min": -10.0,
   "uoc_mess": 860.0
  },
  "outputs": {
   "uoc_soll": 866.05,
   "uoc_max": 978.32,
   "abweichung": 0.7
  }
 },
 "verification": "formula checked against independent test vectors; browser JS equals the reference evaluator",
 "commercial_action": {
  "type": "product_search",
  "label": "Messgeräte ansehen",
  "product_category": "Wechselrichter",
  "store": "eBay.ch",
  "query_template": "PV Installationstester",
  "search_url_template": "https://www.ebay.ch/sch/i.html?_nkw={q}",
  "example": {
   "query": "PV Installationstester",
   "url": "https://www.ebay.ch/sch/i.html?_nkw=PV%20Installationstester"
  },
  "bom": [
   {
    "slot": 1,
    "kind": "primary",
    "label": "Passend zum Ergebnis (Normgröße)",
    "query_template": "PV Installationstester",
    "standard_size_step": 0,
    "search_url_template": "https://www.ebay.ch/sch/i.html?_nkw={q}",
    "example": {
     "query": "PV Installationstester",
     "url": "https://www.ebay.ch/sch/i.html?_nkw=PV%20Installationstester"
    }
   },
   {
    "slot": 2,
    "kind": "accessory",
    "label": "Montagezubehör / Messgerät",
    "query_template": "MC4 Prüfadapter Messleitungen",
    "standard_size_step": 0,
    "search_url_template": "https://www.ebay.ch/sch/i.html?_nkw={q}",
    "example": {
     "query": "MC4 Prüfadapter Messleitungen",
     "url": "https://www.ebay.ch/sch/i.html?_nkw=MC4%20Pr%C3%BCfadapter%20Messleitungen"
    }
   }
  ],
  "standard_series": null,
  "affiliate": false,
  "rel": "sponsored nofollow",
  "note": "Parts list (bom) in display order. Replace {placeholders} in query_template with the user's computed values (inputs or outputs); for placeholders listed in standard_series use the smallest series value >= the computed value, then move standard_size_step positions up the series; URL-encode the query and substitute {q} in search_url_template."
 },
 "api": {
  "endpoint": "https://fachrechner.com/api/v1/calc/bot_021",
  "method": "GET",
  "parameters": "input ids as query parameters (missing = default); response JSON with outputs",
  "free_calls_per_day": 10,
  "auth": null,
  "on_limit": "HTTP 402 daily_limit_reached (no paid tier; quota resets 00:00 UTC, Retry-After)",
  "pro_checkout": null,
  "expression_tree": "https://fachrechner.com/m2m/bot_021.json"
 }
}