Electric Motor Calculator

[{"question":"Why does the recommended breaker size seem high compared to FLC?","answer":"Induction motors draw a high "inrush current" (Locked Rotor Current) during startup, typically 6 to 8 times the Full Load Current (FLC). The calculator suggests breaker sizing based on NEC standards (often 250% for inverse time breakers) to prevent nuisance tripping during this transient phase."},{"question":"What is the difference between IE2 and IE3 efficiency classes?","answer":"IE classes define International Efficiency standards (IEC 60034-30-1). IE3 (Premium Efficiency) motors have lower losses than IE2 (High Efficiency) motors. While IE3 motors are more expensive upfront, they reduce electrical consumption, which lowers the operating amperage and long-term costs."},{"question":"How does the Power Factor affect cable sizing?","answer":"A lower Power Factor (cosφ) results in higher current draw for the same mechanical power output. Since cables must be sized for the total apparent current (kVA), a poor power factor requires thicker cables and larger switchgear."},{"question":"Does this tool account for voltage drop?","answer":"The cable recommender provides a baseline ampacity check (thermal limit). For long cable runs (exceeding 50m), you must verify voltage drop separately to ensure the voltage at motor terminals remains within ±10% of the rating."}]