Schedule 40 vs Schedule 80 PVC Conduit: Differences & NEC Uses
Schedule 40 vs Schedule 80 PVC conduit: same outside diameter, different wall. Fill loss, physical damage rules under NEC 352.12(C) and 300.5(D)(4), and where each is allowed.
Armored Cable (Type AC) vs MC Cable: Differences Explained
Armored cable (Type AC) vs MC cable: the bonding strip, the ground path, wet location limits, ampacity from NEC Table 310.16, and how to tell them apart in the field.
High-Resistance Grounding Explained: How It Works & Where It’s Used
High resistance grounding limits ground-fault current to 5-10 amps so a first fault alarms instead of tripping. How the NGR is sized, and what NEC 250.36 requires.
Minimum Circuit Ampacity (MCA) Explained for Electricians
Minimum circuit ampacity sizes your conductors, not your breaker. The NEC 440.32 and 440.33 formulas, MCA vs MOCP, and how to pick a wire from a nameplate MCA.
How Many Outlets on a 20-Amp Circuit? What the NEC Actually Says
How many outlets on a 20 amp circuit? None in a dwelling — the NEC sets no limit. In commercial work, 13, from the 180 VA per yoke rule in NEC 220.14(I).
Outlet Height From the Floor: NEC Rules and Standard Heights
How high should outlets be off the floor? The NEC sets no minimum; 12–18 in is standard. See the 4 height limits the NEC does enforce, plus heights by room.
Does a Refrigerator Need a Dedicated Circuit? NEC Answer
A dedicated circuit for a refrigerator is permitted by NEC 210.52(B)(1) Ex. 2, not required — but the appliance manual and 110.3(B) usually make it mandatory.
Watts to BTU/hr: Conversion Formula for Electrical Heat Load
Convert watts to BTU/hr by multiplying by 3.412142. Formula, conversion chart, tons of cooling, and how to work out which watts actually become heat.
What Is 14-2-2 (Double-Neutral) Cable and When to Use It
14-2-2 cable holds two hots, two separate neutrals and a ground — two independent 15 A circuits in one jacket. Colours, derating, box fill and when to use it.
Triplex vs Quadruplex Service Cable Explained
Quadruplex has three insulated conductors plus a bare neutral messenger; triplex has two. Construction, ampacity, code names and the NEC rules that apply to each.
Light Switch Height: NEC & ADA Mounting Requirements
Light switch height explained: the 6 ft 7 in. maximum in NEC 404.8(A), the 15-48 in. ADA reach range, and why 48 inches is trade practice and not code.
Ufer Ground (Concrete-Encased Electrode) Explained: NEC 250.52(A)(3)
Ufer ground explained: what NEC 250.52(A)(3) requires of a concrete-encased electrode, rebar vs 4 AWG copper, GEC sizing, and what disqualifies a footing.
