Public evidence

electrical.kva_to_amps

Machine-checked verification for calculation version 1.4.1 · 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· Balanced sinusoidal apparent power only · Protocol · Schema · Production report

Declared partition coverage: PASS · 3/3 declared partitions (kva-a, a-kva, invalid-domain)
Versions: Calculation 1.4.1 · CVP protocol 1.0.0-proposed
CVP identity: 1/1 property · digest 30ff0e4c906e

Verification

Legacy regression suite: 14/14 calculation tests · Production surface contract 2/2

Three distinct suites: educational examples on the calculator page, this legacy regression count (14/14 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 1.4.1 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 1.4.1. CVP 1.0.0-proposed. 3/3 golden · 5/5 CVP boundary · 3/3 invalid · 1/1 property · 1/1 cross-interface · 1/1 CVP contract. digest 30ff0e4c906e.

Golden (oracle-backed) 3 / 3
CVP boundary 5 / 5
Invalid input 3 / 3
Property 1 / 1
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 rejects incomplete input PASS

Fingerprint sha256:064791df5b7084464bec36b077a0839b18289e8d9f869dadebc51ba7a7e7eaef

Input schema sha256:8d77bc785fbe8ad52bc89259ecbc05c2beda9b823bfb6f3452eaf7a177a111c4 · Output schema sha256:34a2ea313a05a759531f6111191ff8ae85d61b2421568ae2258296c8f47512ba · 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: kva-to-amps
Engine: kva-amps
Engine build: 2026-09-10
Evidence core: 2026-09-05T02:35:39.217Z
Rendered: 2026-09-16T22:03:43.705Z
Last reviewed: 2026-08-08

Assumptions

Balanced three-phase when √3 (L-L) mode is selected.
Voltage and current are RMS for AC.
Power factor is not applied — conversion is from apparent power already.

Limitations

Not for unbalanced three-phase
Not for line-to-neutral as a separate UI mode
No power factor on apparent path
V>0 hard — VOLTAGE_MUST_BE_POSITIVE

Sources

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

IEC 60050 — International Electrotechnical Vocabulary — Apparent power (IEV 131-11-41)
Supports: S = U × I definition of apparent power; unit volt-ampere (VA). kVA is the same quantity at 10³ scale. This conversion uses S and RMS voltage, not power factor.
IEEE Std 1459-2025 — Apparent power to current conversion · 2025-05-16 · errata checked
Supports: 1φ I = 1000·S/V; 3φ L-L I = 1000·S/(√3·V)
BIPM SI Brochure (9th edition, version 4.01) — SI base and derived units for ampere, volt, and power · 2026-06 · DOI
Supports: V, A, and VA unit relationships; kilo (k) = 10³ for kVA
NIST Guide to the SI (SP 811) — Ampere and derived power units
Supports: V, A, and VA 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
`1phi-25kVA-220V`	golden	pass	Expected 113.636 · Actual 113.63636363636364
`3phi-50kVA-440V`	golden	pass	Expected 65.61 · Actual 65.60798513518475
`3phi-100kVA-400V`	golden	pass	Expected 144.34 · Actual 144.33756729740645
`1phi-10kVA-230V`	golden	pass	Expected 43.478 · Actual 43.47826086956522
`soft-zero-kva`	golden	pass	Expected 0 · Actual 0
`zero-volts`	boundary	pass	Expected VOLTAGE_MUST_BE_POSITIVE · Actual VOLTAGE_MUST_BE_POSITIVE
`a-kva-100`	golden	pass	Expected 100 · Actual 100.0016854257967
`roundtrip`	golden	pass	Expected 25 · Actual 24.99992
`bad-phase`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`3phi-200kVA-480V`	golden	pass	Expected 240.56 · Actual 240.5626121623441
`neg-kva`	boundary	pass	Expected VALUE_MUST_BE_NON_NEGATIVE · Actual VALUE_MUST_BE_NON_NEGATIVE
`boundary-kva-amps`	boundary	pass	Expected 144.33756729740645 · Actual 144.33756729740645
`boundary-zero-kva`	boundary	pass	Expected 0 · Actual 0
`property-kva-amps`	property	pass	144.33756729740645