Equipment Grounding Conductor Calculator
Calculate proper equipment grounding conductor (EGC) sizes for electrical systems per NEC requirements. Get accurate sizing for safety and compliance.
Step 1: Circuit Details
NEC Requirements
Equipment grounding conductors must be sized per NEC Table 250.122 based on the overcurrent device rating. Minimum size is 14 AWG for copper.
Step 2: Installation Details
Grounding Conductor Purpose
The equipment grounding conductor provides a low-impedance path for fault current, enabling overcurrent devices to operate and clear ground faults.
Equipment Grounding Conductor Calculation Results
Required Grounding Conductor Size
Grounding Conductor Size Options
Sizing Rules
Equipment grounding conductors sized per NEC Table 250.122 must not be smaller than shown. If conductors are increased in size, the EGC must be increased proportionally.
NEC Compliance & Standards
NEC Table 250.122 Reference
Equipment Grounding Conductor Sizing
Table 250.122 specifies minimum size equipment grounding conductors for grounding raceways and equipment based on the rating or setting of automatic overcurrent devices.
| Rating of Overcurrent Device (Amps) | Copper (AWG or kcmil) | Aluminum (AWG or kcmil) |
|---|---|---|
| 15 | 14 | 12 |
| 20 | 12 | 10 |
| 30-60 | 10 | 8 |
| 70-100 | 8 | 6 |
| 110-200 | 6 | 4 |
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