Electrician's quick reference

A planning aid and memory jogger, not the code. Everything here is summarised in my own words from the NEC 2023, with notes where the 2020 edition differs. Check which edition your jurisdiction has adopted and its local amendments — the inspector has the final word.

How to use it

Type in the search box — dryer, 14-50, gfci kitchen, 480 brown, clearance, 60 A, torque — and everything else hides. The chips under it jump to a section. The search words go into the share link, so you can send someone straight to “NEMA 14-50” or “AFCI”.

Wire colours — the usual phase colours for 120/240, 120/208, 277/480 V and the high-leg delta, DC polarity, and the handful of colour rules the code actually makes (neutral, ground, re-marking).
Receptacles — each NEMA configuration drawn as a face, with its voltage, amps, poles and wires and what it is used for. Locking types are drawn schematically.
GFCI and AFCI — where protection is required in homes and elsewhere, the 2023 additions (all kitchen receptacles, the appliance list in 210.8(D), outdoor outlets in 210.8(F)) and how AFCI protection may be provided.
Working space — pick the voltage to ground and condition for the required depth, with the whole table (and the over-1000 V table) and the width, height, entrance and door rules.
Breakers and wire — common pairings for copper NM cable, copper THHN on 75 °C terminals and aluminium, with the reason for each. For anything beyond the common case use the wire size calculator.
Torque — what 110.14(D) asks, practical reminders, and lb-in / lb-ft / N·m conversion.

Print prints whatever the search is showing, so you can print just the receptacle chart.

Other field tools: conduit bending, available fault current, transformers and three-phase, box fill, conduit fill, grounding and bonding, dwelling load, panel schedule, motor circuits, Ohm’s law and the electronics handbook.

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