Electrical reference chart
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.
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
| 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
| 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 |
How to use this chart
Choose the right current source
Motor branch-circuit conductor and protection work may use table current, while overload settings and diagnostics often depend on nameplate current.
Record motor context
Horsepower, voltage, phase, duty, enclosure, service factor, starter type, and drive use determine which calculator path should be used next.
Link to downstream sizing
After the FLC result, route conductor ampacity, overloads, branch-circuit protection, voltage drop, and starter review into the appropriate calculators.
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 workflow
Record 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 motor
A 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.
Related calculators
Full Load Current Calculator
NEC Table 430.248/430.250 motor full load current (FLC) lookup with conductor sizing, overload-basis reminder, and branch-circuit breaker requirements
Motor Current Calculator
Compare NEC table full-load current with formula current, screen starting current, and check preliminary AC motor branch-circuit sizing.
Motor Cable Sizing Calculator
Screen AC motor branch-circuit conductor size with NEC table FLC, ampacity adjustments, termination limits, and branch-circuit voltage drop.
Related charts
HP to Amps Chart
Use this HP to amps chart: 10 HP at 480V 3-phase estimates 11.2A running current; compare nameplate FLA and NEC FLC before sizing.
Breaker Size Chart
Plan breaker size from load category, continuous duty, conductor protection, interrupting rating, equipment listing, and calculator result notes.
Wire Size Chart
Screen conductor size from calculated load, copper or aluminum material, terminal rating, derating, voltage drop, and equipment notes.
Frequently asked questions
These answers explain how to use the chart without turning a quick reference into a final design decision.