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Motor Nameplate Decoder

Screen common NEMA motor nameplate fields with NEC, NEMA, manufacturer, AHJ, and safe-work boundaries

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Motor nameplate kit

Tools for reading, testing, and relabeling motors in the field:

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Decode common AC motor nameplate fields such as horsepower, voltage, full-load amps (FLA), speed, frame, service factor, efficiency, enclosure, insulation class, and NEMA design letter. The app can show local expected-FLA, conductor, frame, insulation, enclosure, design, and efficiency screens, but those rows are source-gap planning prompts. It is not an NEC calculation of record, conductor schedule, conduit fill calculation, overload setting, breaker or fuse selection, starter/VFD approval, replacement approval, inspection approval, troubleshooting procedure, or safe-work authorization.

Pro Tip: Keep the selected motor nameplate, adopted NEC source text, NEMA/manufacturer data, terminal ratings, conductor conditions, OCPD/controller instructions, voltage drop, SCCR/AIC, AHJ requirements, and electrical safety program in separate review notes. This screen helps organize that review; it does not choose the final equipment.

How It Works

  1. Enter Motor Horsepower and Voltage

    Input motor HP, rated voltage, and phase from the nameplate. The local expected-FLA screen is a comparison prompt only; verify the adopted code edition, selected motor, and manufacturer data before design use.

  2. Enter Nameplate Details

    Input FLA, RPM, service factor, efficiency, frame size, enclosure, insulation class, and NEMA design letter. Treat each decoded field as a review note tied to the actual motor record.

  3. Review Local Screens

    Review source-aware FLA deviation, conductor-row, frame, speed, service-factor, insulation, enclosure, design, and efficiency prompts. Do not treat local rows as licensed standard text or manufacturer-certified data.

  4. Separate Code And Product Decisions

    Use adopted NEC text, local amendments, terminal ratings, conductor conditions, standard device sizes, time-current curves, controller/OCPD instructions, and AHJ requirements for final equipment decisions.

  5. Document Remaining Gaps

    Record manufacturer drawings, model and serial data, VFD/starter context, hazardous-location listings, electrical safety controls, and qualified review before replacement, troubleshooting, or energized work.

Built For

  • Electricians collecting nameplate fields before adopted-code and AHJ review
  • Maintenance techs organizing replacement-motor source notes
  • Plant engineers screening motor records before manufacturer review
  • Inspectors and reviewers separating nameplate data from final code decisions
  • Apprentices learning which nameplate fields need source verification
  • Estimators flagging missing manufacturer, code, safety, and product data before takeoff
  • Reliability engineers documenting motor specifications for maintenance records and CMMS

Features & Capabilities

Source-Aware Nameplate Fields

Screens HP, voltage, phase, FLA, RPM, service factor, efficiency, frame, enclosure, insulation, and NEMA design while keeping manufacturer and standard-source gaps visible.

Local FLA And Conductor Prompts

Shows expected-FLA and 125 percent conductor-row prompts for review notes only. It does not choose conductors, raceway, overloads, breakers, fuses, controllers, or standard device sizes.

Frame And Fit Warnings

Shows local frame and shaft cues while warning that shaft, keyway, foot bolt pattern, flange, coupling, enclosure, and manufacturer drawing data control replacement fit.

Service-Factor And Efficiency Boundaries

Flags service-factor and efficiency as selected-motor fields that need manufacturer, DOE/eCFR, NEMA, duty-cycle, ambient, and review context before operating or energy decisions.

Safety And AHJ Gaps

Carries NFPA 70E, OSHA, LOTO, arc-flash, shock, PPE, qualified-person, adopted-code, local-amendment, utility, and AHJ warnings into exports.

Source Pointers In Export

PDF and CSV exports carry the entered nameplate data, local screens, warnings, assumptions, residual gaps, and source-pointer IDs for review notes.

Comparison

Screen Area Local Prompt Must Verify Not A Final Output Typical Review Use
FLA basis Expected local row Adopted code and selected motor Conductor or OCPD sizing Spot missing source data
Conductor row FLA x 125 percent screen Terminal, derating, raceway, voltage drop Wire or conduit selection Review prompt
Frame Shaft cue Manufacturer drawing and fit data Drop-in replacement approval Parts research
Efficiency Label category screen DOE/eCFR and manufacturer records Compliance or savings proof Energy review note
Safety Warning list NFPA 70E, OSHA, site program Work authorization Planning checklist

Assumptions

  • Nameplate fields are interpreted as typed and are not OCR, manufacturer, or field-measurement validated.
  • Expected FLA, conductor, frame, insulation, enclosure, design, and efficiency rows are local source-gap screens.
  • Adopted code, local amendments, manufacturer instructions, terminal ratings, derating, voltage drop, and AHJ requirements are not applied.
  • Service factor and efficiency comments are review prompts, not continuous-overload, energy-savings, or replacement approvals.
  • Electrical safety controls, LOTO, arc-flash, shock, PPE, and qualified-person requirements are outside the calculation.

Limitations

  • Does not certify NEMA MG 1, DOE/eCFR, NEC, IEC, UL, CSA, or manufacturer compliance.
  • Does not select conductors, raceway, overloads, OCPD, controllers, starters, VFDs, disconnects, labels, grounding, or replacement motors.
  • Does not calculate voltage drop, available fault current, SCCR/AIC, time-current coordination, or standard device sizes.
  • Does not verify hazardous-location listings, enclosure ratings, VFD/inverter duty, bearings, cooling, ambient, altitude, duty cycle, or driven-equipment fit.
  • Does not authorize electrical testing, troubleshooting, LOTO, energized work, or safe operation.

References

  1. NFPA 70 (NEC) source pointer for motor-circuit context; local rows are not certified table reproductions.
  2. NEMA MG 1 source pointer for motors and generators; selected motor and manufacturer data still control use.
  3. DOE and eCFR electric-motor source pointers for efficiency and compliance context.
  4. NFPA 70E and OSHA electrical-safety source pointers for safe-work warnings.

Frequently Asked Questions

No. It can show local FLA and conductor-row prompts, but final conductor, raceway, overload, fuse, breaker, controller, disconnect, grounding, labeling, SCCR/AIC, and coordination decisions require adopted code, equipment instructions, AHJ, and qualified review.
Different motor-circuit decisions may use different current bases. This screen helps keep the distinction visible, but the adopted code text, selected motor, controller, overload device, and AHJ requirements control final use.
No. Frame rows are local cues only. Verify shaft diameter, keyway, extension, bolt pattern, flange, enclosure, cooling, bearings, mounting, driven-equipment fit, manufacturer drawings, and qualified review.
No. Efficiency decisions require selected motor records, DOE/eCFR context, manufacturer certification, actual load profile, tariff basis, repair or replacement economics, and qualified review.
No. Electrical troubleshooting and energization require qualified personnel, proper instruments, LOTO or energized-work controls, PPE, arc-flash and shock review, site procedures, and applicable OSHA/NFPA requirements.
Disclaimer: This tool provides preliminary nameplate interpretation and source-boundary prompts only. It is not an NEC calculation of record, licensed standard, manufacturer data sheet, replacement approval, inspection approval, troubleshooting procedure, or safe-work authorization.