How we verify the math

PowerLab sizes conductors, overcurrent protection, batteries, and solar against ABYC E-11, NEC, and CEC (CSA C22.1) values. A wrong number in this kind of tool is not a bug — it’s a hazard. So the engine is built to be checked.

1. Deterministic math, no AI in the number path

Every calculation is a pure function reading explicit, versioned tables. The in-app AI assistant is advisory only — it has no write path into a design and cannot produce a wire size, fuse rating, or compliance claim on its own; those always come from the deterministic engine.

2. Every table cell pinned to published values

The failure mode that internal consistency tests can never catch is a transcription error — a table copied wrong from the standard. So each reference table is verified against independently published sources and locked with transcription tests that fail the build if any cell drifts:

ABYC free-air ampacity, engine-space and bundling factors

Cross-checked against four independent reproductions: the ABYC E-9 (1990) table scan incorporated by reference into US federal law, ABYC E-11 (2008) table excerpts published by Paneltronics, the current Table 6A published by BoatHowTo courtesy of ABYC, and Nigel Calder’s worked tables in Professional BoatBuilder (2018).

ABYC voltage-drop method

Computed on the standard’s own circular-mil method (K = 10.75, round-trip length, 3% critical / 10% non-critical). The engine reproduces the standard’s published worked example exactly.

NEC Table 310.16 ampacity, Chapter 9 conductor resistance, ambient correction factors

Every cell checked against independent reproductions of the printed code tables; small-conductor overcurrent caps (NEC 240.4(D)) enforced in both wire and fuse selection.

CEC (CSA C22.1) Table 2 ampacity and Rule 14-104(2) caps

Verified against two independent Canadian sources plus IAEI guidance on the 2015 NEC/CEC harmonization.

3. Audited, fixed, and locked — July 2026

In July 2026 we ran a full engine audit against those published sources, found table transcription errors in earlier versions, corrected them in the conservative direction, and pinned every affected value with a test that reproduces the original failure. The full calculation suite — table transcription, voltage-drop physics, derating monotonicity, OCPD caps and placement, battery and solar sizing, and adversarial inputs — runs on every change.

4. What we do not claim

PowerLab output is engineering documentation and decision support — it is not a certification, an inspection, or a substitute for a licensed marine technician, electrician, or professional engineer.
ABYC does not certify software. “Built on ABYC E-11” means our tables and methods are verified against published reproductions of the standard — review of the current paywalled editions by a licensed reviewer is in progress, and until it completes we deliberately say “cited to” rather than “compliant.”
Where a jurisdiction requires a stamped drawing, a PE stamp is a separate, per-job step — the report is the design package a PE reviews.

See it for yourself

Run the free calculators against your own numbers, or look at a full example report.

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