What Size Wire for a 100-Amp Service? NEC Sizing Guide
What size wire for a 100 amp service: 4 AWG copper or 2 AWG aluminum per NEC Table 310.12(A). Why #4 copper works, the 83% rule, and where it does not apply.
Kirk Key Interlock Explained: How It Works & When It’s Required
What a Kirk key interlock is, how trapped-key interlocking works, the common schemes it protects, and why it is never a substitute for lockout/tagout under NFPA 70E.
Can a 200 A Breaker Be Your Service Disconnect? NEC Rules
Can a 200A breaker be a service disconnect? What NEC 230.70, 230.71, 230.79 and 230.85 require of a 200 amp disconnect, plus conductor sizing from Table 310.12(A).
NEMA L5-30R Explained: Twist-Lock Receptacle Ratings & Wiring
NEMA L5-30R explained: 125V 30A twist-lock ratings, how to wire it, 10 AWG branch circuit sizing, GFCI rules, and how L5-30 differs from TT-30 and L14-30.
Liquid Tight vs Sealtite: LFMC vs LFNC Conduit Explained
Liquid tight vs sealtite explained: Sealtite is a brand, LFMC and LFNC are the two NEC wiring methods. Article 350 vs 356, fill, length limits and grounding.
60-Amp Sub-Panel: Wire Size, Loads & When It’s Enough (NEC)
60 amp sub panel wire size, EGC sizing, and whether a sub panel size of 60 amp is enough for your load. NEC Table 310.16, 215.3, 250.122 and 408.40 explained.
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.
