@bootsandbolts: ➡️ Single phase (120/240V): two hots + neutral. Nearly every house. ➡️ 208Y/120V three phase: 120 × 1.732 ≈ 208V phase to phase. Apartments, stores, small commercial. ➡️ 480Y/277V: 277V lighting, with no 120V unless you step down through a transformer. Big commercial and industrial. #electrician #electricalapprentice #electricalwork #threephase #electrical