Verified calculation capability

Amps to volts Calculation Capability

Solve voltage from current plus resistance or power, and reverse to current. Watts paths cover DC, AC single-phase, and balanced three-phase L-L. · Electrical

Capability ID electrical.amps_to_volts · version 1.4.2

Open calculator REST API MCP Evidence Evidence JSON CVP Manifest Review policy

Model

With watts (DC)

With watts (DC): V = P ÷ I
With ohms: V = I × R
AC 1φ (watts): V = P ÷ (I × PF)
AC 3φ (watts): V = P ÷ (√3 × I × PF)

Inputs / Outputs

Canonical symbols for this capability. Agent schemas remain the contract.

Symbol	Quantity	Unit	Role
`formula`	—	—	output
`api_version`	—	—	output
`api_contract_version`	—	—	output
`spec_version`	—	—	output
`page`	Canonical calculator page URL	—	output
`links`	—	—	output

Assumptions / Validity

Declared scope for this capability. Do not use it outside this domain.

Assumptions

Ohms path assumes resistive Ohm’s-law behavior.
Watts DC matches P = V·I. Watts AC uses RMS and total power factor λ.
Three-phase watts path assumes balanced line-to-line voltage.
DC does not use power factor or phase. Canonical Agent schema forbids power_factor on DC; REST may send it and it is ignored with POWER_FACTOR_IGNORED.
JSON Schema is a callable-input envelope (types, required fields, enums). Zeros and out-of-range PF may be schema-valid; the engine returns stable error codes.

Not supported

Unbalanced three-phase
converting amps to volts from current alone
reactive impedance networks on the ohms path

Example

One numerical check. The calculator page holds worked steps and FAQ.

120 W ÷ 10 A = 12 V; 2 A × 12 Ω = 24 V

Open this example in the calculator

Trust

CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance. Computational verification is defined by CVP. Supplemental domain review (internal) and named expert review are defined by the Review policy and do not by themselves determine CVP conformance.

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· View Manifest · CVP overview · Specification
Assurance: Engineering
Declared partition coverage: PASS · 8/8 declared partitions (a-v-ohm, v-a-ohm, a-v-watt-dc, a-v-watt-ac_single, a-v-watt-ac_three, v-a-watt, invalid-domain, round-trip)
Calculation version: 1.4.2
Verification: 42/42 calculation tests · 11/11 legacy golden · 20/20 legacy boundary · 11/11 legacy property
Production surface contract: 36/36
Versions: Calculation 1.4.2 · CVP protocol 1.0.0-proposed
CVP identity: 11/11 property · digest b787583c1faa
Reference: O1 model · O2 expected_values · O2 numerical_behavior
Interfaces: PASS · UI (SSR) / REST / MCP
ui-ssr is query-result HTML, not a live browser session.
CVP suite: 7/7 golden · 20/20 CVP boundary · 18/18 invalid · 11/11 property · 2/2 round-trip · 2/2 cross-interface · 36/36 CVP contract
Supplemental domain review: Not performed
Named expert review: Not performed
Version lock: Supported (409 VERSION_MISMATCH)
Artifact consistency: Build verified · 1.4.2 (workspace artifacts agree)
Review-policy tier: Engine tested — catalog token engine_tested; supplemental; not CVP status

This calculator CURRENT · Public schema 1.4.2 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

Call this capability

Human page, REST, and MCP share the same engine and calculation_version. Build verified hashes workspace artifacts only. After deploy, attest:production GETs canonical URLs twice — the public/cached view an Agent actually hits, and origin — including every /capabilities/{id} HTML page. Public Capability HTML version must match catalog before production attestation passes. Live Trust rows above fetch /.well-known/calculatorx-production-attestation.json and the output schema const. Build hashes: release integrity. That proves currently published page / engine / schema / evidence / MCP agree — not that a historical version is independently immutable. Reference Calculation Standard — Production surface contract 36/36.

Tool id: amps-to-volts
Engine: amps-volts
REST: POST /api/v1/calc/amps-to-volts
MCP: execute_calculation with capability_id: "electrical.amps_to_volts"
Agent input schema: Canonical (MCP / Agent)
Output schema: JSON Schema (latest)
Versioned input schema: Immutable pin (1.4.2)
Versioned output schema: Immutable pin (1.4.2)

Operations

Declared calculation modes for this capability.

a-v-ohm
a-v-watt
v-a-ohm
v-a-watt

References

Human-readable sources plus CVP reference evidence classes.

Sources

Watt’s law / power identity — Real power P = V × I × PF (1φ); P = √3 × V × I × PF (3φ L-L)
Ohm’s law — Ohmic conductors V = I × R
IEC 60050 — International Electrotechnical Vocabulary — Active power (IEV 131-11-42)
IEC 60050 — International Electrotechnical Vocabulary — Power factor (IEV 131-11-46)
IEEE Std 1459-2025 — Power factor in AC real-power calculations
BIPM SI Brochure (9th edition, version 4.01) — SI units for ampere, volt, ohm, and watt
NIST Guide to the SI (SP 811) — Volt, ampere, ohm, watt
CalculatorX amps-volts-reference oracle (O2) — Separate-module Node arithmetic — same V8 binary64 runtime as IUT (not language-isolated); scripts/lib/cvp/oracles/amps-volts-reference.mjs

Reference evidence classes: O1 model · O2 expected_values · O2 numerical_behavior

Try with an agent

Inspect this capability via same-origin MCP, then call execute_calculation.

curl -sS -X POST 'https://www.calculatorx.com/mcp' \
  -H 'Content-Type: application/json' \
  -H 'MCP-Protocol-Version: 2026-07-28' \
  -H 'Mcp-Method: tools/call' \
  -H 'Mcp-Name: inspect_capability' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"inspect_capability","arguments":{"capability_id":"electrical.amps_to_volts"}}}'

Inspect the trust tier and required assurance level before execution. Pin calculation_version (1.4.2) when reproducibility matters. Full protocol notes: MCP docs.