Dual 4/0 SER feeders to separate 200A panels from a 320A pedestal — Table 250.66 says size GEC on largest ungrounded conductor, not parallel. Inspector wants 320A service basis. NEC text, table values, and field consensus for #4 vs #2 copper GEC.
July 9, 2026
Water heaters sit near water — so why does NEC not require GFCI like pools under Article 680? The difference between receptacle GFCI rules (210.8), cord-connected appliances (422.5), and hardwired fixed equipment explained for the trade.
July 9, 2026
Power company wants 12 feet over a grass backyard — you thought NEC required 10 feet minimum. NEC 225.18 clearance table explained: pedestrian areas vs residential property vs driveways, and when utility standards exceed NEC.
July 9, 2026
A refrigerator moved 10 feet from the only sink — does NEC require a dedicated circuit, GFCI protection, or can it share one of the two required small-appliance branch circuits? NEC 210.52(B) and 210.8 analyzed with a decision chart.
July 9, 2026
Five current-carrying conductors in a raceway trigger Table 310.15(C)(1) derating. A continuous motor branch circuit triggers 125% conductor sizing per 430.22. Here is how both rules apply to #12 THHN feeding a 14-amp motor — with NEC tables and a worked example.
July 9, 2026
