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Category: Electrician careers, career change & licensing

HVAC and Appliance Circuits (NEC 440 and 422): Reading MCA and MOCP, Water Heaters and Disconnects

How to size an air conditioner circuit from the nameplate MCA and MOCP, why a water heater circuit is sized at 125%, where the disconnect goes, and two worked examples…

Updated 2026-10-12 · Read the article ›

NEC 404, 406 and 410: Receptacles, Switches and Luminaires for Apprentices

Learn the 2026 NEC rules for receptacles, switches, luminaires and ceiling fan support, including replacement receptacles, switch-box neutrals, damp and wet locations, and 180 VA receptacle load calculations for Texas…

Updated 2026-10-17 · Read the article ›

Underground Wiring and Burial Depth (NEC 300.7, formerly 300.5): Cover Depths, Driveways and Protection Where It Comes Up

How deep to bury cable and conduit under the NEC, what "cover" means, the shallower depths for GFCI residential circuits, driveways and parking areas, warning ribbon, wet-location conductors and protection…

Updated 2026-10-12 · Read the article ›

Service Equipment for Apprentices (2026 NEC): Meter, Main Disconnect, Panel and Neutral-to-Ground Bonding

How a residential electrical service is put together, from the utility point to the main disconnect and panelboard: what counts as service equipment, where neutral and ground are bonded, why…

Updated 2026-10-12 · Read the article ›

Voltage Drop Calculation for Apprentices: The 3% and 5% Recommendations, Chapter 9 Table 8 and Sizing Up a Long Run

How to calculate voltage drop on a single-phase or three-phase circuit with Chapter 9 Table 8 resistance values, what the NEC's 3% and 5% informational notes mean, and a worked…

Updated 2026-10-12 · Read the article ›

NEC 705 and 706 for Apprentices: Connecting Solar and Batteries to a Panel, Supply-Side Taps, the 120% Rule and Disconnects

How Articles 705 and 706 treat interconnected power sources and energy storage: supply-side and load-side connections, the 120% busbar rule with a worked 200 A panel example, disconnecting means, shutdown…

Updated 2026-10-12 · Read the article ›

NEC 517 for Apprentices: Patient Care Spaces, Redundant Grounding, Receptacles at the Bed and the Essential Electrical System

What Article 517 asks of wiring in hospitals and other health care facilities: the four patient care space categories, redundant grounding, receptacle counts and branch circuits at general care and…

Updated 2026-10-17 · Read the article ›

NEC 511 and 514 for Apprentices: Repair Garages, Fuel Dispensers, Classified Areas, Seals and Emergency Disconnects

How the NEC treats commercial repair garages and motor fuel dispensing facilities: why the floor area can be a Class I location, the classified zone around a fuel dispenser, conduit…

Updated 2026-10-12 · Read the article ›

NEC 424 and 426 for Apprentices: Baseboard Heaters, the 125% Rule, Heater Disconnects and Snow-Melting Cable

How the NEC treats fixed electric space heating and outdoor deicing equipment: sizing the branch circuit at 125%, baseboard heaters and receptacles, disconnects and thermostats, and ground-fault protection for snow-melting…

Updated 2026-10-12 · Read the article ›

NEC 408 Panelboards for Apprentices: Circuit Directories, Overcurrent Protection, Backfed Breakers and the High Leg

What Article 408 asks of panelboards and switchboards: a clear circuit directory, source marking, overcurrent protection for the panel, backfed breaker fasteners, closing unused openings, and the high leg on…

Updated 2026-10-12 · Read the article ›
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Not a licensed Professional Engineer in Texas or any U.S. state. Does not offer engineering services. Exam-prep education only.