WireGaugeCalc Free calculator · NEC cited · works offline
Aluminum Cable For 500 Foot Electrical Service Run
Aluminum cable for 500 foot electrical service run sizing is fast with WireGaugeCalc, since you enter the service amps, the conductor material, and the 500 foot length and the calculator returns the aluminum size.
It checks NEC 310.16 ampacity against your termination temperature column, then it adds voltage drop over the long run so the wire is not undersized.
You get an aluminum size that carries the service load and still lands inside the 3% drop guideline at 500 feet.
Open the calculatorSmallest conductor whose ampacity meets the load, NEC Table 310.16. Field aid only, verify against the current NEC and your local authority having jurisdiction.
Why A 500 Foot Aluminum Service Run Needs Voltage Drop Math
A 500 foot run is long, so voltage drop usually controls the size before ampacity does.
Aluminum has higher resistance than copper, so the same amps over 500 feet drop more volts and often push you up a size.
WireGaugeCalc compares the ampacity-based size against the drop-based size and shows the larger of the two.
What WireGaugeCalc Checks For A Long Aluminum Service Run
Sizing aluminum service conductors over 500 feet depends on a few inputs:
- Service amps and single or three phase
- Aluminum conductor, since resistance differs from copper
- The 500 foot one-way run length
- Termination temperature column at 75C unless rated otherwise
- NEC 310.16 ampacity for the chosen aluminum size
- Voltage drop held near the 3% branch-circuit guideline
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
What aluminum size carries a 200A service over 500 feet?
Ampacity alone allows 250 kcmil aluminum at 75C for a 200A service, but voltage drop over 500 feet usually forces you larger, often to 350 kcmil or more. Run your exact load and length in the calculator and verify the result against the current NEC and your local authority having jurisdiction.
Does voltage drop matter more than ampacity at 500 feet?
Yes, at 500 feet voltage drop typically sets the size since the long run adds resistance, so the drop-based size is larger than the ampacity-based size.
Why is aluminum larger than copper for the same service?
Aluminum has higher resistance per foot than copper, so for the same amps and length it drops more voltage and needs a larger conductor.
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.