Side-by-Side Comparison
Electrical & Wiring
Electrical Wire Color Codes vs. Electrical Boxes
Comparing 2 standards across 22 specifications. 22 key differences identified.
Comparing:
Electrical Wire Color Codes
Electrical Boxes
AC electrical wiring color codes distinguish Line (hot), Neutral, and Ground conductors, standardized in the US under NEC (120/240V Black/Red/White and 277/480V Brown/Orange/Yellow) and internationally under IEC 60446 (Brown/Black/Grey Line, Blue Neutral, Green-Yellow Ground).
Standard electrical outlet and junction boxes are specified by trade dimensions and minimum internal cubic inch volume, including 4-inch square boxes (1900/1920 boxes, 21.0–30.3 cu in), 4-inch octagon ceiling boxes (15.5–21.5 cu in), and single-gang device boxes (18.0 cu in).
Specification Comparison Table
22 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Standards
|
NEC Article 200/250 (US) / IEC 60446 / BS 7671 (Europe/UK) | NEMA OS 1 / NEC Article 314.16 |
|
US 120V / 240V Phase A (Hot)
|
Black | — |
|
US 120V / 240V Phase B (Hot)
|
Red | — |
|
US 120V / 208V Phase C (Hot 3-Phase)
|
Blue | — |
|
US 120V / 240V Neutral
|
White (Continuous white or gray outer finish per NEC 200.6) | — |
|
US 277V / 480V Commercial 3-Phase (Wye)
|
Phase A: Brown | Phase B: Orange | Phase C: Yellow | Neutral: Gray (conventional scheme; this is a symmetrical wye system with no high-leg condition) | — |
|
US 120V / 240V High-Leg Delta (4-Wire, 3-Phase)
|
Phase A: Black | Phase B: Orange (NEC 110.15-mandated high-leg marking, ~208V to neutral) | Phase C: Blue | Neutral: White | — |
|
US Protective Earth / Ground
|
Bare Copper, Green, or Green with Yellow Stripe | — |
|
IEC / Europe Phase 1 (L1)
|
Brown | — |
|
IEC / Europe Phase 2 (L2)
|
Black | — |
|
IEC / Europe Phase 3 (L3)
|
Grey | — |
|
IEC / Europe Neutral (N)
|
Blue (Light Blue) | — |
|
IEC / Europe Protective Earth (PE)
|
Green with Yellow Stripe (Bi-color mandate) | — |
|
4" Square Box (1-1/2" Deep–1900 Box)
|
— | 4.0 × 4.0 × 1.5 in (102 × 102 × 38 mm) | 21.0 cu in (344 cm³) |
|
4" Square Box (2-1/8" Deep–1920 Box)
|
— | 4.0 × 4.0 × 2.125 in (102 × 102 × 54 mm) | 30.3 cu in (496 cm³) |
|
4" Octagon / Round Ceiling Box
|
— | 4.0 × 4.0 × 1.5 in (102 × 102 × 38 mm) | 15.5 to 21.5 cu in |
|
Handy / Utility Box (Surface 2×4")
|
— | 4.0 × 2.125 × 1.875 in | 13.0 to 14.5 cu in |
|
Single-Gang Plastic Device Box
|
— | Standard 18.0 to 22.5 cu in (supports up to 9 × 14 AWG conductors) |
|
Double-Gang Plastic Device Box
|
— | Standard 32.0 to 35.0 cu in |
|
Volume Allowance per 14 AWG Conductor
|
— | 2.00 cu in (32.8 cm³) per wire |
|
Volume Allowance per 12 AWG Conductor
|
— | 2.25 cu in (36.9 cm³) per wire |
|
Volume Allowance per 10 AWG Conductor
|
— | 2.50 cu in (41.0 cm³) per wire |
Other Alternatives to Compare
Compare Electrical Wire Color Codes vs. AWG Wire Sizes →
Compare Electrical Wire Color Codes vs. Circuit Breaker Sizes & Amperage →
Compare Electrical Wire Color Codes vs. Electrical Conduit →
Compare Electrical Wire Color Codes vs. Electrical Conduit Fill Capacity →
Compare Electrical Wire Color Codes vs. Wire Ampacity Ratings →