Public evidence

electrical.transformer_sizing

Machine-checked verification for calculation version 1.0.0 · 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· Ideal lossless transformer; no magnetizing current · Protocol · Schema · Production report

Declared partition coverage: PASS · 4/4 declared partitions (ratio, va, current, invalid-domain)
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed
CVP identity: 2/2 property · digest a4a1bbe624c5

Verification

Legacy regression suite: 7/7 calculation tests · Production surface contract 3/3

Three distinct suites: educational examples on the calculator page, this legacy regression count (7/7 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 1.0.0 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 1.0.0. CVP 1.0.0-proposed. 3/3 golden · 2/2 CVP boundary · 1/1 invalid · 2/2 property · 1/1 cross-interface · 1/1 CVP contract. digest a4a1bbe624c5.

Golden (oracle-backed) 3 / 3
CVP boundary 2 / 2
Invalid input 1 / 1
Property 2 / 2
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 sha256:126857d7f05e657625aca33f824937c61bf37030c81b62b305ca22659254e2fa

Input schema sha256:7b1e7e421f474d00ad0349882e095fb62eb05d32d582469929f65b9d9d15fac6 · Output schema sha256:17155b5d5cfc2ffeb6a4c78e8f9384d8648aecfde0599eacd6b33d684b65f7ee · 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: transformer-sizing
Engine: transformer-sizing
Engine build: 2026-09-10
Evidence core: 2026-09-06T13:16:40.891Z
Rendered: 2026-09-16T22:03:43.728Z
Last reviewed: 2026-08-08

Limitations

Ideal lossless single-phase

Sources

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

IEC 60076 — Power transformers (concepts) — Ideal transformer ratios
Supports: Voltage/turns and VA basics
Chapman — Electric Machinery Fundamentals — Ideal transformer
Supports: Vp/Vs = Np/Ns and VA conservation

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
`ratio`	golden	pass	Expected Ns=10 · turns_ratio=10 · Actual mode=ratio · Vp=240 · Vs=24 · Np=100 · Ns=10 · turns_ratio=10
`va`	golden	pass	Expected S_VA=2400 · S_kVA=2.4 · Actual mode=va · V=240 · I=10 · S_VA=2400 · S_kVA=2.4
`current`	golden	pass	Expected Is=10 · Actual mode=current · Ip=1 · Is=10 · Np=100 · Ns=10 · current_ratio=0.1
`needs3`	boundary	pass	Expected NEEDS_THREE_INPUTS · Actual NEEDS_THREE_INPUTS
`boundary-xf-va`	boundary	pass	Expected S_VA=2400 · Actual mode=va · V=240 · I=10 · S_VA=2400 · S_kVA=2.4
`property-ns`	property	pass	Ns=10
`property-va`	property	pass	2400 VA