WireGaugeCalc Free calculator · NEC cited · works offline
HP to FLA
HP to FLA is quick with WireGaugeCalc, since you enter the horsepower, voltage, and phase and read the full load amperes.
It pulls the value from the NEC motor full load current tables so the FLA matches what you size conductors and overloads to.
You get the amps in one step, so you can move to wire and overcurrent sizing.
Open the calculatorEnter any two values and read the rest.
Ohm’s law: V = I × R and P = V × I. Field aid only, verify against the current NEC and your local authority having jurisdiction.
Reading 10 HP Motor FLA from the Tables
A 10 HP motor FLA depends on voltage, so a 10 hp 480v motor draws about 14 amps from the three-phase table.
The NEC uses table values, not the nameplate, for sizing conductors and branch-circuit protection, since the table builds in a margin.
The calculator returns the listed FLA for your inputs so the rest of the circuit lines up.
FLA for Common 480 Motor Amps
Enter the motor details and the tool returns the FLA, for example:
- FLA for 2 hp at 460 vac, around 3 amps
- 10 hp 480v motor amps, around 14 amps
- Single-phase versus three-phase values
- 208, 230, and 460 volt options
- Nameplate amps for comparison
One app for every NEC calculation
WireGaugeCalc keeps the calculations you reach for most in one place:
- Voltage drop and wire sizing for any run
- Conduit fill for EMT, PVC, and RMC
- Box fill and junction box sizing
- Ampacity and temperature derating
- Motor circuit and load calculations
- Conduit bend offsets and saddles
Built for the field, works offline
The whole app runs on your phone, so it keeps working in a basement, an attic, or a job site with no signal.
There is no account to create and nothing to load. Open it, run the number, and get back to work.
- No signup and no signal needed
- Answers in a tap, not a spreadsheet
- Same tool on phone, tablet, and desktop
Every result cites the NEC article
Each answer shows the table or formula it came from, so you can check the method and learn the code as you go.
That makes the app useful on the job and during exam prep, since the reasoning is right next to the number.
Switch the code year your job runs on
Jurisdictions adopt the NEC at different times, so you can match the calculation to the code in force:
- NEC 2017, 2020, and 2023 tables
- Copper and aluminum conductors
- 60, 75, and 90 degree C terminations
- Single-phase and three-phase systems
Run the number, then get back to work
Stop flipping through a paper book or hopping between calculator sites. Enter your values, read the code-cited answer, and move on. Free to use, no signup.
Open the calculatorFrequently asked questions
Should I use nameplate amps or table FLA for sizing?
Use the NEC table full load current to size branch-circuit conductors and short-circuit protection, since the table value is required for that math. Use the nameplate amps to set the overload device.
Why does the FLA drop at higher voltage?
Power stays the same while voltage rises, so the current falls, which is why a 2 hp motor at 460 vac draws fewer amps than at 230. Always confirm the table value against the current NEC and your local authority having jurisdiction.
Is WireGaugeCalc free to use?
Yes. Every calculator is free to run with no signup. A paid tier adds saved projects, PDF reports, and extra code years, but the core math stays free.
Does it work without internet?
Yes. The app runs on your device, so it keeps working with no signal on a job site, in a basement, or in an attic.
Are the results code accurate?
Results follow published NEC tables and standard formulas, and each answer shows the article it came from. It is a field aid, not a stamp of approval, so verify against the current code and your local authority before you wire anything.
Which NEC code year does it use?
You can switch between NEC 2017, 2020, and 2023, since jurisdictions adopt the code at different times. Pick the year your job runs on.