Intry Verified receipt

Is the Intry Three-Phase Motor Calculator accurate and NEC compliant?

The provenance receipt for the Intry Three-Phase Motor Calculator: the exact authority its values derive from, the edition they are keyed to, who has final say, and what our automated checks hold them against, rebuilt from their cited source.

The receipt

Calculated from

NEC 2023 Table 430.250, Full-Load Current, Three-Phase AC Motors · NEC 2023 Table 430.248, Full-Load Currents, Single-Phase AC Motors · NEC 2023 430.6(A)(1), which current to use · NEC 2023 430.22 and Table 310.16, the conductor · NEC 2023 430.52(C)(1) with Table 430.52, and 240.6(A) standard ratings · NEC 2023 240.4(G) and Table 240.4(G), why a motor branch circuit may sit under a larger breaker (NEC 2023). Reused verbatim from the locked engine, never re-written for this page.

Checked

Before any release, an automated check rebuilds the calculated figures from the locked engine that produces them and holds each one against the source it cites, so a number answers to its source and not merely to itself. As of the current build that suite holds 29291 checks, and this page has to clear them too. This is our own deterministic gate, not a third-party audit.

Runnable

A reference engine behind the published numbers on this site. Runnable access is offered on the calculators exposed at the Intry MCP endpoint.

Final say

Your AHJ has final say. The table current sizes the branch circuit; your motor's nameplate sizes the running overload device (430.32), which this tool does not size. Wound-rotor and DC motors take a different percentage from Table 430.52 and are out of scope.

Frequently Asked Questions

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