Definition
Equipment Grounding Conductor (EGC) is the dedicated conductor that bonds all metallic electrical equipment to the grounding electrode system, providing a low-impedance fault current path. Sized per NEC 250.122 Table based on OCPD rating.
NEC 250.122 EGC Sizing
| OCPD (A) | Copper EGC | Aluminum EGC |
|---|---|---|
| 15 | 14 AWG | 12 AWG |
| 20 | 12 AWG | 10 AWG |
| 30–60 | 10 AWG | 8 AWG |
| 100 | 8 AWG | 6 AWG |
| 200 | 6 AWG | 4 AWG |
| 400 | 3 AWG | 1 AWG |
Key Takeaways
- EGC = safety grounding conductor.
- Sized per NEC 250.122 by OCPD rating.
- Bonds all metallic equipment to ground.
- NEC 690.45(B) may require larger than 250.122 minimum.
- Always copper for solar source circuits.
Frequently Asked Questions
2 commonly searched questions about EGC (Equipment Grounding Conductor).
What is an EGC?
Equipment Grounding Conductor — dedicated conductor bonding metallic equipment (module frames, racking, conduit, inverter chassis) to grounding electrode for safety.
EGC sizing?
Per NEC 250.122. 15 A OCPD: 14 AWG. 20 A: 12 AWG. 30–60 A: 10 AWG. 100 A: 8 AWG. NEC 690.45(B) may require larger for solar.
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