Motor Full Load Amps Chart

Use this motor full load amps chart after the FLC calculator result to document which current value feeds conductor sizing, overload settings, breaker review, and voltage-drop screening.

Open calculator

Quick reference table

Motor full-load amps are source-dependent. Code table FLC, nameplate FLA, and formula estimates can support different decisions, so the worksheet should keep them separate before conductors, overloads, breakers, starters, VFDs, or motor cable are selected under the adopted NEC edition, manufacturer instructions, and AHJ review.

Motor current source worksheet

Motor current source worksheet
Current source	Use for planning	Do not use it for
Code table FLC	Branch-circuit conductor and short-circuit protection screens	Nameplate overload settings without checking motor data
Nameplate FLA	Overload and equipment-specific review	Replacing every table-current branch-circuit step
Formula estimate	Early load screening before exact motor data is available	Final motor protection or conductor selection
Starting current estimate	Voltage drop, generator, and starter method review	Steady-state conductor ampacity by itself
Drive output current	VFD or drive-specific conductor and protection review	Ignoring drive manufacturer instructions

Motor result-area follow-up

Motor result-area follow-up
After calculator result	Field decision	Related check
FLC lookup completed	Branch-circuit conductor screen	Wire size and ampacity charts
Nameplate FLA recorded	Overload device setting and service factor review	Motor starter or protection worksheet
High starting current expected	Voltage dip, generator, or reduced-voltage starting review	Motor starting current chart
VFD used	Drive input and output protection path	Manufacturer manual and equipment listing

Formula basis

Formula estimate: A = HP x 746 / (voltage x efficiency x power factor), with the three-phase estimate also divided by 1.732.

HP is motor horsepower from the schedule or nameplate.
Efficiency and power factor are assumptions unless measured or listed by the manufacturer.
FLC table values, nameplate FLA, and formula estimates can control different downstream steps.

Worked examples

10 HP pump motor workflowRecord HP, voltage, phase, duty, nameplate FLA, and starter type, then use the FLC calculator for branch-circuit current while keeping overload and starter decisions tied to nameplate data.

VFD-fed fan motorA VFD project needs input current, output current, motor nameplate data, carrier and cable instructions, and drive manual notes kept together before conductor or protection choices are made.

Assumptions. Balanced load and line-to-line voltage assumptions behind this chart.

This chart does not reproduce NEC motor FLC tables.
Motor sizing paths can differ for special motors, VFD outputs, multispeed motors, fire pump work, elevators, and manufacturer-specific equipment.
Formula estimates are early planning aids and should not replace table lookup, nameplate data, or listed equipment instructions.

Code and standard notes. Planning limits that should be checked before final equipment selection.

Verify motor current and protection with the adopted NEC edition, motor nameplate, manufacturer instructions, local amendments, and the Authority Having Jurisdiction (AHJ).
Do not mix table FLC, nameplate FLA, and formula estimates without documenting which downstream decision each value supports.

How to use this chart

1Choose the right current sourceMotor branch-circuit conductor and protection work may use table current, while overload settings and diagnostics often depend on nameplate current.

2Record motor contextHorsepower, voltage, phase, duty, enclosure, service factor, starter type, and drive use determine which calculator path should be used next.

3Link to downstream sizingAfter the FLC result, route conductor ampacity, overloads, branch-circuit protection, voltage drop, and starter review into the appropriate calculators.

Worksheet checklist. Record source basis, review gaps, and assumptions before using the chart result.

Record motor schedule dataWrite HP, voltage, phase, duty, enclosure, service factor, starter type, VFD status, and nameplate current when those values are available.
Separate FLC and FLAMark whether each downstream decision uses code table current, nameplate full-load amperes, starting current, or a planning formula estimate.
Add protection workflowDocument conductor ampacity, overload device setting, branch-circuit protection, starting behavior, and drive manufacturer requirements.

Common mistakes to avoid. Review these before turning chart current into an equipment decision.

Using nameplate current for every motor sizing step when a code table current may control some branch-circuit decisions.
Using a horsepower formula estimate as the final motor full-load current without checking the adopted NEC edition and nameplate data.
Combining overload protection, branch-circuit short-circuit protection, and starter selection into one breaker-size decision without documenting the motor path.

Frequently asked questions

These answers explain how to use the chart without turning a quick reference into a final design decision.

Is FLC the same as nameplate FLA?

Not necessarily. FLC table values and nameplate FLA can be used for different parts of the motor workflow, so the worksheet keeps them separate.

Can I use the HP formula for motor protection?

Use the formula only for preliminary screening. Motor protection and conductor decisions should be verified with the calculator, nameplate, adopted NEC edition, and AHJ requirements.

Why does starting current appear on a full-load amps page?

Starting current does not replace full-load current, but it affects voltage drop, generator sizing, starter selection, and nuisance-trip review, so it belongs in the workflow notes.