WireGaugeCalc Free calculator · NEC cited · works offline
55kW 480V Motor FLA
55kw 480v motor fla is fast to estimate with WireGaugeCalc.
The calculator converts the rated power to amps at 480 volts three phase, then aligns it with the NEC full load current values, so you size conductors and protection from a real number.
You get the working full load amps before you spec the feeder.
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.
From Kilowatts To Full Load Amps
A 55kW motor sits near 75 horsepower, so its full load current at 480 volts three phase lands around 96 amps from the NEC table.
The calculator uses the NEC table value rather than the nameplate for conductor sizing, since the code requires that approach for branch circuits.
It also handles smaller frames, so a 15hp motor current at the same voltage comes out near 21 amps for comparison.
Inputs Behind The FLA
Enter the motor data that sets the current:
- Rated power in kilowatts or horsepower
- System voltage of 480 volts
- Phase, single or three phase
- NEC full load current table value
- Service factor for downstream sizing
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
Do I use the nameplate amps or the NEC table for sizing?
Use the NEC full load current table for sizing the branch circuit conductors and overcurrent. Use the nameplate amps for setting the overload protection. Verify both against the current NEC and your local authority having jurisdiction.
What is the full load current of a 15hp motor at 480V?
A 15hp three phase motor at 480 volts draws roughly 21 amps from the NEC table. The calculator returns the exact table value for each rating.
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.