Public evidence

electrical.watt_volt_amp

Machine-checked verification for calculation version 1.5.1 · tier expert_verified

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· Resistive DC identities; soft-zero on ÷0 · Protocol · Schema · Production report

Declared partition coverage: PASS · 4/4 declared partitions (pair-vi, with-power, with-R, invalid-domain)
Versions: Calculation 1.5.1 · CVP protocol 1.0.0-proposed
CVP identity: 5/5 property · digest 937dea566d45

Verification

Legacy regression suite: 17/17 calculation tests · Production surface contract 3/3

Three distinct suites: educational examples on the calculator page, this legacy regression count (17/17 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.5.1 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Calculation version 1.5.1. CVP 1.0.0-proposed. 4/4 golden · 4/4 CVP boundary · 4/4 invalid · 5/5 property · 1/1 cross-interface · 1/1 CVP contract. digest 937dea566d45.

Golden (oracle-backed) 4 / 4
CVP boundary 4 / 4
Invalid input 4 / 4
Property 5 / 5
Cross-interface 1 / 1
CVP contract 1 / 1
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS

Fingerprint sha256:23bd4c102728349653307344d5879056aed7badf077c049d9d683bb91babcba1

Input schema sha256:bc49ebb92a15d482954fc73412070f669f8ccacc9667b4ace21e613c8ba12d8e · Output schema sha256:2bff83a1041be8c7a8cffcea93ccc74e7d0d2c8b882a5bfe394dd201b3a0f55a · 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: watt-volt-amp
Engine: watt-volt-amp
Engine build: 2026-09-10
Evidence core: 2026-09-05T02:35:39.217Z
Rendered: 2026-09-16T22:03:43.703Z
Last reviewed: 2026-08-08

Assumptions

Ohmic resistance; RMS for AC
First two filled fields define the known pair

Limitations

Resistive model only
Fewer than two inputs throws; zero divisors yield 0 for dependents

Sources

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

NIST Guide to the SI (SP 811) — Watt, volt, ampere, and ohm relationships in the SI
Supports: P = V·I; V = I·R; derived forms for P+R pairs
IEC 60050 — International Electrotechnical Vocabulary — Resistance (IEV 131-12-04)
Supports: R = u/I for a resistive two-terminal element; V = I·R and derived P+R forms
IEC 60050 — International Electrotechnical Vocabulary — Active power (IEV 131-11-42)
Supports: P is active power; unit watt (W). For ohmic DC, P = V·I
BIPM SI Brochure (9th edition, version 4.01) — SI units for volt, ampere, ohm, and watt · 2026-06 · DOI
Supports: V, A, Ω, W coherent unit relationships

Legacy published checks

Golden and boundary cases from the legacy Evidence JSON. CVP property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the Manifest — including SKIP when a suite has no vectors.

ID	Kind	Status	Detail
`V+I`	golden	pass	Expected P=1200 · R=12 · Actual P=1200 · V=120 · I=10 · R=12
`P+V`	golden	pass	Expected I=10 · R=12 · Actual P=1200 · V=120 · I=10 · R=12
`I+R`	golden	pass	Expected V=120 · P=600 · Actual P=600 · V=120 · I=5 · R=24
`P+R`	golden	pass	Expected V=200 · I=0.5 · Actual P=100 · V=200 · I=0.5 · R=400
`linear-2x-V`	golden	pass	Expected P=2400 · R=24 · Actual P=2400 · V=240 · I=10 · R=24
`soft-zero-V`	golden	pass	Expected P=0 · R=0 · Actual P=0 · V=0 · I=10 · R=0
`soft-zero-R`	golden	pass	Expected V=0 · I=0 · Actual P=50 · V=0 · I=0 · R=0
`error-single-input`	boundary	pass	Expected NEEDS_TWO_INPUTS · Actual NEEDS_TWO_INPUTS
`error-empty`	boundary	pass	Expected NEEDS_TWO_INPUTS · Actual NEEDS_TWO_INPUTS
`P+I`	golden	pass	Expected V=120 · R=24 · Actual P=600 · V=120 · I=5 · R=24
`nan-V`	boundary	pass	Expected INVALID_NUMBER · Actual INVALID_NUMBER
`boundary-single-wva`	boundary	pass	Expected NEEDS_TWO_INPUTS · Actual NEEDS_TWO_INPUTS
`property-VI`	property	pass	V,I → P,R
`property-PV`	property	pass	P,V → I
`property-IR`	property	pass	I,R → V,P
`property-PR`	property	pass	P,R → V,I
`property-roundtrip`	property	pass	V,I → R → V,R recovers I