Screening use onlyResults are educational estimates. They are not verified for construction, equipment selection, or permit submission.· 1 registered heuristic group (H-008)Why

These calculators are undergoing a correctness audit against primary standards. Part of the logic still rests on engineering rules-of-thumb rather than rules traced to a dated edition of a code, and some published citations do not yet match the rule the code actually applies. Known defects are being fixed in sequence.

Treat every number here as a starting estimate to be checked, never as a design decision. Anything that will be built, energised, or submitted to an authority must be independently calculated and sealed by a licensed engineer who takes responsibility for the result.

Audit status: in progress · Assurance level: screening · Not for permit use

Rule-of-thumb decisions on this calculator

H-008 · forbid permit
Decision points: built-in kW series used as the screening catalog candidate
Motor screening refuses missing efficiency, power factor, service factor, temperature and altitude derating and starting multipliers, and reports the service factor rather than folding it into the sizing. The only value the engine still chooses is the built-in kW candidate series, disclosed in the result as an unverified catalog list.
Permit gate: block

Screening use only — Results are educational estimates. They are not verified for construction, equipment selection, or permit submission.

These calculators are undergoing a correctness audit against primary standards. Part of the logic still rests on engineering rules-of-thumb rather than rules traced to a dated edition of a code, and some published citations do not yet match the rule the code actually applies. Known defects are being fixed in sequence.

Treat every number here as a starting estimate to be checked, never as a design decision. Anything that will be built, energised, or submitted to an authority must be independently calculated and sealed by a licensed engineer who takes responsibility for the result.

Audit status: in progress · Assurance level: screening · Not for permit use

Rule-of-thumb decisions on this calculator

H-008 · forbid permit
Decision points: built-in kW series used as the screening catalog candidate
Motor screening refuses missing efficiency, power factor, service factor, temperature and altitude derating and starting multipliers, and reports the service factor rather than folding it into the sizing. The only value the engine still chooses is the built-in kW candidate series, disclosed in the result as an unverified catalog list.
Permit gate: block

CALC 10 · MOTORSPREVIEW

Motor Sizing Screening

I = P ÷ (√3 × V × PF × η)

Motor Sizing · Advanced Preview

Available free during the correctness audit. Results remain screening-only unless the result itself states a stronger assurance level.

Manufacturer Data Required

This tool will not invent nameplate efficiency, power factor, derating, or starting-current multipliers. Enter values from the actual motor and controller data.

LOAD AND SUPPLY

Required Mechanical Load *

Line Voltage *

V

Phases *

Common supply presets

NAMEPLATE DATA

Efficiency (η) *

Use the actual motor nameplate or manufacturer data.

Power Factor *

Use the rated-load nameplate/manufacturer value.

Service Factor *

Displayed for review only. It is not multiplied into the required motor output.

MANUFACTURER DERATING

Ambient *

°C

Altitude *

m

Temperature Factor *

Capacity multiplier from the selected motor manufacturer.

Altitude Factor *

Capacity multiplier from the selected motor manufacturer.

STARTING-CURRENT DATA

DOL Multiplier *

× FLC

Star-Delta Multiplier *

× FLC

Soft-Starter Multiplier *

× FLC

SCREENING RESULT

— AWAITING VERIFIED INPUT —

Complete every required field using load-study, nameplate, and manufacturer data.

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