CVP verified calculation capability

Amps to kW Calculation Capability

Convert current and voltage to real power in kW (or reverse) for DC, single-phase AC, and balanced three-phase L-L.

Electrical Capability ID electrical.amps_to_kw version 1.4.3 CVP VERIFIED CURRENT Engineering

Model

DC: kW = I × V ÷ 1000
AC 1φ: kW = PF × I × V ÷ 1000
AC 3φ (L-L): kW = √3 × PF × I × VL-L ÷ 1000
AC 3φ (L-N) — reference only: kW = 3 × PF × I × VL-N ÷ 1000

Modes: a-kw · kw-a

Inputs / Outputs

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

Symbol	Quantity	Unit	Role
`current_a`	Phase current in amperes	—	input
`voltage_v`	Voltage	—	input / output
`system`	dc = DC	—	input / output
`power_factor`	Required for AC	—	input / output
`power_kw`	Real power in kilowatts	—	input
`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

Balanced three-phase when AC 3φ (L-L) is selected.
Voltage is RMS for AC.
DC does not use power factor. AC uses total power factor λ on real power.

Not supported

Unbalanced three-phase
L-N three-phase as a selectable mode (reference formula only)

Example

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

20 A, 400 V, PF 0.9, AC 3φ → 12.471 kW

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 · 10/10 declared partitions (a-kw-dc, a-kw-ac_single, a-kw-ac_three, kw-a-dc, kw-a-ac_single, kw-a-ac_three, invalid-domain, round-trip, metamorphic, near-singularity)
Calculation version: 1.4.3
Verification: 16/16 calculation tests · 8/8 legacy golden · 3/3 legacy boundary · 5/5 legacy property
Production surface contract: 36/36
Versions: Calculation 1.4.3 · CVP protocol 1.0.0-proposed · Evidence 2026-09-10.evidence-semantics
Verification revision: 2026-09-10.evidence-semantics · 5/5 property · digest 1fc8b58b8507
Reference: O1 model · O2 expected_values · O2 numerical_behavior
Numerical scope: ≤2 ULP vs this O2 module on the published golden, near-singularity boundary, round-trip, and metamorphic vectors. Computational fidelity: ULP vs O2. Engineering interpretation: exact deterministic algebraic model; measurement uncertainty is outside calculator scope. Not a whole-domain guarantee (overflow, denormals, or unlisted V→0 neighborhoods). O2 shares Node/V8 binary64 with the IUT; O3 is not required this wave.
Interfaces: PASS · UI (SSR) / REST / MCP
ui-ssr is query-result HTML, not a live browser session.
CVP suite: 7/7 golden · 4/4 CVP boundary · 6/6 invalid · 5/5 property · 6/6 metamorphic · 6/6 round-trip · 1/1 cross-interface · 2/2 cross-calculator · 34/34 CVP contract
Supplemental domain review: Internal · Pass · electrical-engineer
Named expert review: Not performed
Version lock: Supported (409 VERSION_MISMATCH)
Artifact consistency: Build verified · 1.4.3 (workspace artifacts agree)
Review-policy tier: Internally reviewed — catalog token internally_reviewed; supplemental; not CVP status

This calculator CURRENT · Public schema 1.4.3 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.

curl -sS -X POST 'https://www.calculatorx.com/api/v1/calc/amps-to-kw' \
  -H 'Content-Type: application/json' \
  -d '{"inputs":{"mode":"a-kw","current_a":12,"voltage_v":120,"system":"ac_single","power_factor":1},"calculation_version":"1.4.3"}'

{
  "inputs": {
    "mode": "a-kw",
    "current_a": 12,
    "voltage_v": 120,
    "system": "ac_single",
    "power_factor": 1
  },
  "calculation_version": "1.4.3"
}

POST /api/v1/calc/amps-to-kw. This is a POST calculate endpoint — do not GET it.

Full REST contract: REST API docs.

Tool id: amps-to-kw
Engine: amps-kw
REST: POST /api/v1/calc/amps-to-kw
MCP: execute_calculation with capability_id: "electrical.amps_to_kw"
Agent input schema: Canonical (MCP / Agent)
Output schema: JSON Schema (latest)
Versioned input schema: Immutable pin (1.4.3)
Versioned output schema: Immutable pin (1.4.3)

Operations

Declared calculation modes for this capability.

a-kw
kw-a

References

Human-readable sources plus CVP reference evidence classes.

Sources

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

Try with an agent

Inspect, then execute. Same engine as REST and the human calculator.

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_kw"},"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientInfo":{"name":"calculatorx-docs-example","version":"1.0.0"},"io.modelcontextprotocol/clientCapabilities":{}}}}'

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: execute_calculation' \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"execute_calculation","arguments":{"capability_id":"electrical.amps_to_kw","inputs":{"mode":"a-kw","current_a":12,"voltage_v":120,"system":"ac_single","power_factor":1},"calculation_version":"1.4.3"},"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientInfo":{"name":"calculatorx-docs-example","version":"1.0.0"},"io.modelcontextprotocol/clientCapabilities":{}}}}'

Pin calculation_version (1.4.3) when the result must stay reproducible.

Inspect the trust tier and required assurance level before execution. Full protocol notes: MCP docs.