NEC Code
PVC Conduit Explained: A Practical Guide to NEC Article 352
A practical guide to NEC Article 352: the five types of PVC conduit, support spacing, expansion fittings, field bends, bushings and exam navigation tips.
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Study tips, exam guides, and everything you need to know about NEC certification.
Calculations
How to Calculate Voltage Drop: The 2KID/CM Formula Explained
Learn the voltage drop formula 2KID/CM step by step, including K factors, NEC Chapter 9 Table 8 circular mils and a full worked exam example.
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Grounding
Mobile Homes – Do You Need a Grounding Electrode System at the Home?
Does a mobile home need its own grounding electrode system, or only the service? Here's how 250.32(A), 550.16 and 550.32(A) fit together.
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Residential
Do Water Heaters Require a Local Disconnect? What the NEC Actually Says
Learn when the NEC requires a local disconnect for water heaters and how 422.31(B) lets your breaker or switch do the job instead.
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Calculations
Applying Conductor Ampacity Adjustments and Corrections
Learn when to count current-carrying conductors, how to apply NEC 310.15 adjustment and correction factors, and which ambient temperature table to use.
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Calculations
The 83% Rule: Sizing Dwelling Services and Feeders – Lesson 9.4
Learn how to size overcurrent devices and conductors for commercial and dwelling services, including when the NEC 83% rule and Table 310.12 apply.
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NEC Code
Electrical Metallic Tubing Explained – EMT – Article 358
A practical walk through NEC Article 358: where EMT can be used, corrosion rules, support and securing distances, bends, and exam tips.
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Grounding
Ufer Ground: How to Properly Connect and Install a Concrete-Encased Electrode
Learn the two NEC-approved ways to install a Ufer ground: bond to the footing rebar or lay 20 feet of bare No. 4 copper in the concrete.
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Residential
General Receptacle Placement in Dwellings: The 6-Foot/12-Foot Rule Explained
How NEC 210.52(A) sets general receptacle spacing in dwelling units: the 6/12 rule, what counts as wall space, floor boxes and outlets that don't count.
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Calculations
Ampacity and OCPD Sizing: Breaker First, Then Wire (Lesson 9.3)
Learn the exam-proven order for sizing overcurrent protection and conductors, with five worked examples covering continuous and non-continuous loads.
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Exam Tips
How to Pass the Journeyman Electrician Exam: A Code Panel Member's Approach
A 40-year NEC veteran and code panel member explains why structured study, not pamphlets or video-only courses, is what gets you through the journeyman exam.
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Residential
Receptacles in Shower Spaces: NEC Changes from 2017 to 2023
How NEC 406.9(C) evolved from 2017 to 2023 — the 3 ft by 8 ft zone, small bathroom exceptions, and the new bidet receptacle allowance.
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Calculations
How to Calculate Minimum General-Use Receptacle & Lighting Circuits
A step-by-step guide to sizing the minimum 15- or 20-amp general lighting and receptacle circuits for a dwelling using NEC 220.41.
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Calculations
How to Size Wire for Continuous and Non-Continuous Loads
Learn to size conductors for continuous and non-continuous loads using the NEC ampacity tables, terminal ratings, and the 125% rule.
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NEC Code
Rigid Metal Conduit (RMC) Explained — NEC Article 344
A practical walk through NEC Article 344: where RMC is permitted, corrosion rules, bushings, bends, securing and supporting, and grounding.
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Residential
Do Smoke Detectors Require a Dedicated Circuit?
The NEC doesn't require a dedicated circuit for hardwired smoke detectors — here's why that's a good thing, and where to tap the circuit from instead.
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Grounding
SSBJ vs EGC: What's the Difference and Why It Matters
A CMP-5 member explains the difference between supply side bonding jumpers and equipment grounding conductors under the 2023 NEC, including how to size each.
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Calculations
Box Fill Basics: How to Calculate Box Volume the Right Way
A practical walk-through of NEC 314.16 box fill: conductors, equipment grounds, clamps, devices, barriers and a full worked example.
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Residential
Where Are AFCI Breakers Required? NEC 210.12 Explained
A room-by-room guide to where NEC 210.12 requires AFCI protection in dwelling units — and the exceptions most electricians miss.
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NEC Code
Raceway Fill Explained: Using NEC Informative Annex C and Chapter 9 Tables
Learn two ways to work out conductor fill — the fast Informative Annex C lookup and the full Chapter 9 Table 1, 4 and 5 calculation.
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Calculations
General Demand Factors for Whole House Load Calculations – NEC Table 120.45
Learn how to apply NEC Table 120.45 demand factors to general lighting, receptacle, small appliance and laundry loads in dwelling units.
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Residential
Hot Tub Code Violations Debunked: What NEC 2023 Article 680 Really Says
A master electrician critiques five common hot tub code claims — separating real NEC 2023 Article 680 requirements from widespread myths.
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NEC Code
3 Types of Surge Protection Explained: Type 1, Type 2, and Type 3 SPDs
Understand Type 1, Type 2 and Type 3 surge protective devices — where each installs, what it protects against, and why modern homes need layered protection.
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Special Topics
Fault Current Compliance: What NEC 110.9 & 110.10 Mean for Your Service Equipment
Understand available fault current, SCCR, and AIC ratings under NEC 2023 sections 110.9, 110.10 and 110.24 for commercial service equipment.
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Grounding
When NOT to Drive a Ground Rod at a Detached Building
NEC 250.32(A) explained: why a single branch or multi-wire branch circuit to a detached garage doesn't require a grounding electrode system.
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Calculations
Sizing the Neutral Conductor in Dwelling Load Calculations
Learn why the neutral conductor in a single-family dwelling must be sized under NEC Part III, and how to apply every allowance correctly.
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Calculations
Range Load Calculations Explained: NEC 220.55 and 120.55
A step-by-step guide to calculating range and cooking-appliance loads for dwellings using NEC Table 220.55 (120.55 in the 2026 code), Columns A–C.
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NEC Code
MC Cable Explained: A Practical Guide to NEC Article 330
A working electrician's plain-English guide to metal-clad cable under NEC Article 330: where you can use it, where you can't, and the common mistakes.
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NEC Code
Rigid Metal or PVC Through the Roof? NEC Article 230 Overhead Service Drops Explained
A practical guide to NEC Article 230 overhead service drops: PVC under the eave versus rigid metal through the roof, plus the 230.24 conductor heights.
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Residential
GFCIs and Tankless Water Heaters: What the 2023 NEC Actually Requires
A working electrician's breakdown of why tankless water heaters don't need GFCI protection under the 2023 NEC — and how the real rules of 210.8 and 422.5 work.
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Calculations
Dryer Load Calculations Made Simple: NEC Section 220.54 and Table 220.54
A step-by-step guide to calculating household dryer loads for the exam using the NEC's 5,000 VA minimum rule and the demand factors in Table 220.54.
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Grounding
EGC vs EBJ: How to Size Equipment Grounds and Bonding Jumpers in the Box
A working electrician's guide to equipment grounding conductors versus equipment bonding jumpers, and how the 2023 NEC changes tying grounds in the box.
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Grounding
When to Drive a Ground Rod at a Detached Building
A clear, code-based explanation of when you must establish a grounding electrode system at a detached building or outbuilding fed from another structure.
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Calculations
2026 NEC Article 120: Mastering the 2 VA Per Square Foot Load Calculation
A practical walkthrough of NEC Article 120 dwelling load calculations: the 2 VA per square foot rule, what counts as square footage, and exam tips.
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NEC Code
AC Cable Explained – A Working Electrician's Guide to Article 320
A practical breakdown of NEC Article 320 armoured cable: how Type AC differs from MC, where you can run it, and the bonding strip and ampacity rules.
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Grounding
How to Size Grounding Electrode Conductors Using NEC Table 250.66
A step-by-step guide to sizing grounding electrode conductors with NEC Table 250.66, including the parallel-conductor trick and the electrode exception.
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Exam Prep
Master Electrician Exam Prep: How to Spot a Wrong Answer in a Box Fill Question
A 40-year NEC instructor shows how a box fill question can carry the wrong answer key, and why you should always challenge your study source.
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Calculations
Transformer Calculations 101: Turn Ratios and Overcurrent Protection Made Simple
A practical guide to transformer turn ratios, primary and secondary currents, and NEC 450.3(B) overcurrent protection for the journeyman and master exams.
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NEC Code
2026 NEC Change to 250.122: What Electricians Need to Know About EGC Sizing
A plain-English guide to the 2026 NEC 250.122 changes for sizing equipment grounding conductors on standard, parallel, motor, and feeder-tap circuits.
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Exam Tips
The #1 Strategy for Beating Your Electrical Exam
A working electrician's exam-day strategy for beating the testing algorithm, managing stress, and maximising your journeyman or master's exam score.
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AFCI
AFCI Rules When Extending or Modifying Branch Circuits
Learn when extending or modifying an existing branch circuit triggers AFCI protection under NEC 210.12, and when the 6-foot exception applies.
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Residential
Top 10 NEC Articles Every Residential Electrician Should Memorise (Part 1)
A working electrician's breakdown of the first five must-know NEC articles for residential work — from Article 100 definitions to receptacle spacing in 210.52.
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Voltage Drop
Where Is Voltage Drop Required and What Does the IECC Say?
A clear breakdown of where the NEC actually mandates voltage drop, where it's only a recommendation, and how the IECC quietly requires it for commercial work.
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Residential
Dishwasher and Disposal on the Same Circuit? The Truth About the 50% Rule
Can a dishwasher and garbage disposal share one branch circuit? Here's what NEC 210.23 actually says and why the 50% rule is so misunderstood.
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NEC Code
Multiwire Branch Circuits: How to Wire Them Safely Under the NEC
A clear, code-based guide to multiwire branch circuits: what they are, how to install them properly, and how to avoid mistakes that burn up neutrals.
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Load Calculations
Full Whole House Load Calculation Walkthrough (2026 NEC)
A step-by-step breakdown of a complete residential dwelling load calculation using the 2026 NEC — general lighting, fixed appliances, dryer, range, and HVAC.
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Calculations
How to Size Water Heater Wire and Breakers Using the NEC
A practical guide to sizing branch-circuit conductors and overcurrent protection for a residential electric water heater under the NEC's min and max rules.
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Grounding
Pool Bonding 101 – Understanding Equipotential Bonding for Permanently Installed Pools
A practical guide to equipotential bonding for permanently installed pools: what must be bonded, bonding methods, and key NEC 680.26 requirements.
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NEC Code
Emergency Disconnects for One and Two Family Dwellings — NEC 230.85 Explained
A complete breakdown of NEC 230.85 emergency disconnect rules for one and two family dwellings: your three options, marking, and 2020-to-2023 changes.
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AFCI
AFCI Breaker Nuisance Tripping: Causes & Troubleshooting
Why AFCI breakers nuisance trip, the most common wiring and appliance causes, and a step-by-step troubleshooting method for electricians.
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NEC Code
MC Cable vs AC Cable: What Every Electrician Needs to Know
A clear breakdown of MC cable versus AC cable: armour construction, equipment grounding, and healthcare rules under NEC Articles 320, 330, and 517.
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NEC Code
Surge Protection Code Changes: What Changed From NEC 2017 to 2023
A breakdown of NEC surge protection rules in 230.67 across the 2017, 2020, and 2023 cycles, from voluntary to mandatory for dwelling units and beyond.
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Exam Prep
Why Some Practice Questions Are 'Wrong' — and Why That's OK
A deep dive into how even professional exam prep databases get NEC questions wrong, and what electricians can learn from dissecting those mistakes.
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Grounding
When and Why to Separate Grounds and Neutrals
A clear breakdown of when grounds and neutrals must be bonded versus separated, why it matters for safety, and what happens when you get it wrong.
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Exam Prep
How to Tab the 2026 Electrical Code Book – Ultimate Guide Page by Page
A complete page-by-page guide to tabbing your 2026 NEC codebook so you can find any article, table, or section in seconds during your electrical exam.
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Calculations
Raceway Fill with Mixed Conductor Sizes – NEC Chapter 9 Explained
A step-by-step guide to calculating raceway fill with different conductor types and sizes, one of the most common NEC exam calculation questions.
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How One Electrician Passed the Journeyman Exam on the First Try
Real-world advice from an electrician who passed the journeyman exam on his first attempt: no costly courses, just a proven way to learn the NEC.
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Exam Tips
How to Pass the NEC Exam: A Complete Guide
Everything you need to know about preparing for and passing your National Electrical Code certification exam, from study strategies to exam day tips.
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Exam Topics
Top NEC Exam Topics You Must Know
A breakdown of the most heavily tested NEC topics across all electrician licensing exams, with tips on what to focus your study time on.
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Licensing
NEC Exam Types Explained: Journeyman, Master, and More
Understanding the different types of NEC-based electrical licensing exams, their requirements, and how to choose the right preparation path.
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Technical
Understanding NEC Grounding and Bonding: Article 250 Deep Dive
A comprehensive guide to NEC Article 250 covering grounding electrode systems, equipment grounding, bonding requirements, and common exam questions.
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