WireGaugeCalc Free calculator · NEC cited · works offline
Ground Wire Size For 50 Amp Sub Panel
Ground wire size for 50 amp sub panel is fast with WireGaugeCalc, since the tool reads the breaker rating and returns the grounding conductor from NEC 250.122.
You pick the conductor material, so the result matches a copper or aluminum equipment grounding conductor.
The payoff is a correctly sized ground for the feeder before you set the lugs.
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.
Sizing The 50 Amp Sub Panel Ground
The equipment grounding conductor is sized from the 50 amp overcurrent device per NEC 250.122, so the breaker rating drives the result.
A 50 amp feeder calls for a 10 AWG copper grounding conductor under NEC 250.122, while aluminum steps up one size.
Switching the material updates the gauge, since aluminum needs more area than copper for the same rating.
What The 50 Amp Ground Depends On
The sub panel grounding conductor depends on:
- The 50 amp breaker rating per NEC 250.122
- Conductor material, copper or aluminum
- A separate grounding conductor since neutrals and grounds split at a sub panel
- Any upsizing if the feeder conductors are increased
- The four-wire feeder run to the sub panel
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 ground wire size do I use for a 50 amp sub panel?
NEC 250.122 calls for a 10 AWG copper equipment grounding conductor for a 50 amp overcurrent device. Aluminum steps up to 8 AWG. Verify against the current NEC and your local authority having jurisdiction.
Do I separate the ground and neutral in a 50 amp sub panel?
Yes, at a sub panel the grounding and grounded conductors must stay separate, and the neutral bar is isolated from the enclosure. The bonding screw is removed and a four-wire feeder is run.
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.