https://lmxforge.com Electrical engineering articles and calculation guides from LMXFORGE. en-us Sun, 26 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/transformer-application-engineering https://lmxforge.com/articles/transformer-application-engineering Impedance, cooling classes (ONAN/ONAF), vector groups, inrush current, and selection checklist for distribution transformer applications. Sun, 26 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/ground-grid-design-basics https://lmxforge.com/articles/ground-grid-design-basics Touch voltage, step voltage, soil resistivity testing, grid resistance, and conductor sizing for substation earthing systems — IEEE 80 method. Thu, 23 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/mcc-schedule-fundamentals https://lmxforge.com/articles/mcc-schedule-fundamentals How to build an MCC schedule from the motor list — bucket sizing, starter selection, feeder and bus sizing, and NEC vs IEC coordination requirements. Thu, 16 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/cable-tray-fill-sizing https://lmxforge.com/articles/cable-tray-fill-sizing How to calculate cable tray fill and apply ampacity derating — NEC Article 392 percentage-fill tables and IEC 60364-5-52 grouping factor methods, with worked guidance. Thu, 16 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/cable-ampacity-derating https://lmxforge.com/articles/cable-ampacity-derating How to apply temperature correction and grouping factors to cable ampacity — NEC Table 310.16 and IEC 60364-5-52 methods, with worked examples. Wed, 01 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/demand-load-calculation https://lmxforge.com/articles/demand-load-calculation How to calculate demand load from connected load — demand factors, diversity factor, design margin, and power factor conversion for transformer and switchgear sizing. Wed, 01 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/motor-starting-protection https://lmxforge.com/articles/motor-starting-protection Starting current, torque, voltage dip, and protection requirements for DOL, star-delta, soft starter, and VFD starting methods — NEC and IEC reference. Wed, 01 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/short-circuit-calculations https://lmxforge.com/articles/short-circuit-calculations How to calculate short circuit fault current using the MVA method and impedance method — worked examples, motor contribution, and NEC vs IEC differences. Wed, 01 Jul 2026 00:00:00 +0000 https://lmxforge.com/articles/voltage-drop-lv-cable-runs https://lmxforge.com/articles/voltage-drop-lv-cable-runs Step-by-step voltage drop calculation for LV systems — single-phase and three-phase, NEC and IEC methods, with worked examples including motor starting voltage dip. Mon, 15 Jun 2026 00:00:00 +0000 https://lmxforge.com/articles/cable-schedule-fundamentals https://lmxforge.com/articles/cable-schedule-fundamentals Cable Schedule Fundamentals — Structure, Sizing Logic, and Standards — a practical engineering guide from LMXFORGE. Mon, 01 Jun 2026 00:00:00 +0000 https://lmxforge.com/articles/duct-bank-conduit-sizing https://lmxforge.com/articles/duct-bank-conduit-sizing A practical guide to sizing conduit configurations for underground duct bank systems — covering NEC and IEC approaches for electrical engineers. Mon, 01 Jun 2026 00:00:00 +0000 https://lmxforge.com/articles/load-summary-fundamentals https://lmxforge.com/articles/load-summary-fundamentals Load Summary Fundamentals — Demand Factors, Diversity, and Sizing Logic — a practical engineering guide from LMXFORGE. Mon, 01 Jun 2026 00:00:00 +0000 https://lmxforge.com/articles/motor-list-fundamentals https://lmxforge.com/articles/motor-list-fundamentals What goes into a motor list, how it relates to load summaries and cable schedules, and where IEC and NEC practice diverge. Mon, 01 Jun 2026 00:00:00 +0000 https://lmxforge.com/articles/mv-lv-distribution-design https://lmxforge.com/articles/mv-lv-distribution-design How to design MV/LV distribution systems — feeder sizing checks, fault level calculations, selectivity methods, cable derating, and key NEC vs IEC differences. Mon, 01 Jun 2026 00:00:00 +0000