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Motor Circuit Calculator

Estimate motor conductor size, overload setting, and branch short-circuit/ground-fault protection for common Canadian motor circuits.

Inputs

Use motor table full-load current for conductors and branch short-circuit/ground-fault protection. Use nameplate FLA for overload setting when available.

Advanced Settings

Results

Status
Estimate Ready
Verify final motor circuit design with the current code, nameplate data, and AHJ.
Recommended Wire Size
-
Motor Table FLC
0.0 A
Minimum Conductor Ampacity
0.0 A
Overload Setting
0.0 A
Max Branch SC/GF Protection Calc
0.0 A
Suggested Standard Protection Size
-

Calculation Details

    Shop Wire & Cable Shop Breakers & Fuses Ask Arkco to Verify This Motor

    Motor Circuit Notes

    Table FLC
    Conductors and branch short-circuit/ground-fault protection are typically based on motor table full-load current, not necessarily nameplate FLA.
    Overload
    Overload protection is typically based on motor nameplate current and motor service-factor/temperature-rise conditions.
    347V Single Phase
    347V single-phase motor values are estimated from 230V table current. Verify unusual motor voltages with the motor nameplate and manufacturer data.
    Not For All Motors
    Do not use this alone for VFDs, multi-speed motors, hermetic refrigerant motors, fire pumps, elevators, or equipment with MCA/MOCP markings.
    Disclaimer
    This calculator is provided as a general estimating tool only. Results are based on simplified assumptions and common motor-circuit sizing methods. It does not replace engineering review, manufacturer data, motor nameplate requirements, the Canadian Electrical Code, local amendments, or approval by the authority having jurisdiction. Arkco Electrical Supply is not responsible for design decisions, installation outcomes, or code compliance based on this calculator.

    © 2026 Arkco Electrical Supply. This calculator is provided for Arkco customers and may not be copied or republished without written permission.