{
  "url": "https://openlegislation.uk/meters-certification-regulations-1990/schedule-1/paragraph-10",
  "json_url": "https://openlegislation.uk/meters-certification-regulations-1990/schedule-1/paragraph-10.json",
  "legislation": "uksi/1990/792",
  "legislation_title": "The Meters (Certification) Regulations 1990",
  "legislation_url": "https://openlegislation.uk/meters-certification-regulations-1990",
  "path": "schedule/1/paragraph/10",
  "kind": "paragraph",
  "number": "10",
  "heading": "Insulation property test",
  "text": "Each meter shall be tested to demonstrate that the insulation of the meter is of a sufficient standard to enable the meter to operate safely and correctly in the conditions in which it could reasonably be expected to be installed and operated.\nTABLE 1\nInfluence quantities\nReference value\nTolerance\nAmbient temperature\nReference temperature or, if not indicated, 23°C.\n>15°C to <30°C\nMeter position\nVertical\n±3°\nVoltage\nReference voltage\n±1.5%\nFrequency\nReference frequency 50Hz\n±0.5%\nVoltage and current waveform\nSinusoidal form\nDistortion factor <5%\nExternal magnetic induction at the reference frequency (paragraph 5.4)\nZero\nInduction value that does not produce a relative error variation of more than& ±0.3%\nTABLE 2\nTest load in terms of marked current\nTest No. & load\nPower factor\nBasic/maximum\nMaximum continuous\nLong range\nShort range\nMeter type\nPolyphase meter load\nNote 1 Where a range is given, any value within that inclusive range may be selected.\nNote 2 For maximum continuously rated prepayment meters, the low load test value may be twice the value shown.\nNote 3 For test no. 4 & 6, the inductive power factor shall be between 0.45 and 0.55 inclusive.\n1 (high)\n1\nImax\n100%\n100%–200% (Note 1)\n100%–125% (Note 1)\nSingle & polyphase\nBalanced\n2 (intermediate)\n1\nIb or 125%IB\nAny load between 25%–75% of the value specified for Test No. 1\nSingle & polyphase\nBalanced\n3 (low)\n1\n5%Ib\n1.67% (note 2)\n5%\n5%\nSingle & polyphase\nBalanced\n4 (inductive)\n0.5\nIb or Imax\n100%\nThe same value selected for Test No. 1\nSingle & polyphase\nBalanced\n5 (element)\n1\nIb\n100%\nThe same value selected for Test No. 1\nPolyphase\nOne phase loaded in turn\n6 (inductive) (element)\n0.5\nIb\n100%\nThe same value selected for Test No. 1\nPolyphase\nOne phase loaded in turn\n7 (starting-current)\n1\n0.5%Ib to 1.0%Ib\n0.5% to 1.0%\n0.5% to 1.0%\n0.5% to 1.0%\nSingle & polyphase\nBalanced",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1990/792/schedule/1/paragraph/10",
    "retrieved_at": "2026-10-29T15:22:08.525435+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}