Standard Value Finder (E-series) implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t7-051

Effect

Computation or source lookup only

Input and validation requirements

The specification does not define behavior for zero or negative targets, has no supported decade bounds for the zero limit, and leaves the meaning of the tolerance input ambiguous. The tolerance probe can produce either no qualifying value or a 12-ohm/15-ohm tie depending on convention.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "target_value": 4700,
    "target_unit": "ohm",
    "series": "E12",
    "tolerance_percent": 5
  },
  "expected_outputs": {
    "nearest_standard_value_ohm": 4700,
    "normalized_value": 4.7,
    "decade_multiplier": 1000,
    "absolute_error_ohm": 0
  },
  "reference_data": {
    "series": "E12",
    "normalized_values": [
      4.7
    ],
    "decade_multiplier": 1000,
    "source_convention": "IEC 60063 preferred-number series; widely tabulated standard value"
  },
  "working": "1. The E12 table contains normalized value 4.7.\n2. Apply the decade multiplier: 4.7 × 1000 = 4700 ohm.\n3. Compare with the target: |4700 - 4700| = 0 ohm.\n4. Therefore the nearest nominal is 4700 ohm (4.7 kohm). The 5% tolerance does not alter nominal selection under the stated assumption."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche7/tranche7-results.json