Public evidence

electrical.power

Machine-checked verification for calculation version 1.3.0 · tier engine_tested

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Verification

26/26 calculation tests · Production surface contract 1/1

Golden tests 14 / 14
Boundary tests 7 / 7
Property tests 5 / 5
Production surface contract 1 / 1
Engine tested Yes
Source checked Yes
Artifact integrity PASS
Production attestation Embedded snapshot: STALE · Last attested schema matched 1.3.0 snapshot / local build · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · Public/cache ✓ · Origin ✓ · Live production status PASS (0 stale; 164 CURRENT) @ 2026-09-16T06:44:24.909Z
Semantic contract PASS
Evidence attested at 2026-09-16T06:44:24.203Z
Last production check 2026-09-16T06:44:24.203Z
Public / cache PASS
Origin PASS
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS

Fingerprint sha256:9fa7e190c6ae1b9eb54a06a2deec231491e27bdbfe5791cee757f494cb632c56

Input schema sha256:2e541d9c0ab753ca0b0140f198ccdec21056ab1f12cc61f59078c2cb5c22c6c7 · Output schema sha256:f6df0c7463bbd2fff8bf0bc4c2ba6082e86d1558b9597b25c8dc670a80c83bcc · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: power
Engine: electric-power
Engine build: 2026-09-12
Evidence core: 2026-09-12T23:10:59.103Z
Rendered: 2026-09-16T22:03:43.703Z
Last reviewed: —

Assumptions

Three-phase path uses balanced line-to-line RMS voltage.
PF on the V×I path is total power factor λ = |P|/S in [0, 1]; blank PF defaults to 1.
I²R path assumes resistive power dissipation (I + R inputs). V²/R is the Ohm’s-law identity, not a third tab.
Energy path is average power P = E/Δt with Δt > 0.

Limitations

V×I path is real power P, not apparent power S (use amps-to-va)
Three-phase is balanced sinusoidal L-L only
I²R tab is I+R only; V²/R is Ohm’s law, not a third tab
PF blank → 1; PF=0 → P=0; PF outside [0,1] → INVALID_POWER_FACTOR
Δt ≤ 0 → INVALID_TIME_INTERVAL (not a soft 0 W)
Sinusoidal PF teaching model; true PF with harmonics is not computed

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

Watt’s law / power identity — Real power P = V × I × PF (1φ); P = √3 × V × I × PF (3φ L-L)
Supports: P from V×I path with phase and PF
Joule heating / Ohm’s law forms — P = I²R = V²/R for resistive dissipation
Supports: P from I²R mode
Energy–power relation — Average power P = E / Δt (J/s → W)
Supports: P from energy mode
IEC 60050 — International Electrotechnical Vocabulary — Active power (IEV 131-11-42)
Supports: P is active power; unit watt (W). V×I path computes P, not apparent power S.
IEC 60050 — International Electrotechnical Vocabulary — Power factor (IEV 131-11-46)
Supports: λ = |P| / S; AC V×I path multiplies by λ
IEEE Std 1459-2025 — Power factor and real vs apparent power · 2025-05-16 · errata checked
Supports: PF on AC V×I path; power triangle context
BIPM SI Brochure (9th edition, version 4.01) — SI units for watt, volt, ampere, and joule · 2026-06 · DOI
Supports: W = J/s; DC P = V·I; P = I²R = V²/R for ohmic dissipation
NIST Guide to the SI (SP 811) — Watt as joule per second
Supports: W = J/s; SI relationships for V, A, Ω, W

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`5V-2A`	golden	pass	Expected 10 · Actual 10
`230V-10A`	golden	pass	Expected 2300 · Actual 2300
`120V-10A`	golden	pass	Expected 1200 · Actual 1200
`I2R`	golden	pass	Expected 2.5 · Actual 2.5
`I2R-2x-I`	golden	pass	Expected 10 · Actual 10
`3phi`	golden	pass	Expected 12470.77 · Actual 12470.765814495917
`from-energy`	golden	pass	Expected 1 · Actual 1
`linear-2x-V`	golden	pass	Expected 4600 · Actual 4600
`linear-half-PF`	golden	pass	Expected 1150 · Actual 1150
`soft-zero-V`	golden	pass	Expected 0 · Actual 0
`soft-zero-I`	golden	pass	Expected 0 · Actual 0
`pf-zero-is-zero-power`	golden	pass	Expected 0 · Actual 0
`pf-gt-1`	boundary	pass	Expected INVALID_POWER_FACTOR · Actual INVALID_POWER_FACTOR
`pf-negative`	boundary	pass	Expected INVALID_POWER_FACTOR · Actual INVALID_POWER_FACTOR
`zero-dt-invalid`	boundary	pass	Expected INVALID_TIME_INTERVAL · Actual INVALID_TIME_INTERVAL
`zero-energy-zero-dt-invalid`	boundary	pass	Expected INVALID_TIME_INTERVAL · Actual INVALID_TIME_INTERVAL
`named-vi-fields`	golden	pass	Expected 1840 · Actual 1840
`named-three-ll`	golden	pass	Expected 12470.766 · Actual 12470.765814495917
`boundary-dt-negative`	boundary	pass	Expected INVALID_TIME_INTERVAL · Actual INVALID_TIME_INTERVAL
`boundary-neg-R`	boundary	pass	Expected VALUE_MUST_BE_NON_NEGATIVE · Actual VALUE_MUST_BE_NON_NEGATIVE
`boundary-blank-pf-default`	boundary	pass	Expected 2300 · Actual 2300
`property-vi`	property	pass	230×10
`property-pf0`	property	pass	PF=0 → 0 W
`property-3phi`	property	pass	3φ L-L
`property-i2r`	property	pass	I²R
`property-energy`	property	pass	E/Δt