Electrical Learning Guides — NEC Explained

The most fundamental relationship in electrical circuits. Learn the three formula forms, the power equations (Watt's Law), and how Ohm's Law drives voltage drop and wire sizing.

Understand the 3% and 5% NEC rules, the voltage drop formula (VD = 2KIL/CM), worked examples, and max run-length tables for common wire gauges.

How to read NEC Table 310.15(B)(16), choose the right temperature column (60/75/90°C), apply derating for ambient temperature and bundled conductors, and compare copper vs aluminum.

Step-by-step NEC 210.20 and 240.6 sizing rules. Learn standard breaker sizes, the continuous load 125% rule, and sizing for dryers, ranges, EV chargers, HVAC, and subpanels.

The difference between ground fault and arc fault protection — what each detects, where the NEC requires each (210.8 and 210.12), and when to use a dual-function breaker.

Decode MCA, MOCP, FLA, RLA, LRA, voltage, phase, HP and PF. Learn how nameplate values determine minimum wire size and maximum breaker size for HVAC, motors, and appliances.