Practical Electrical Guides

Clear, actionable sizing procedures, worked examples, pro tips, and common pitfalls to avoid.

6 min read

How to Calculate Electrical Power: Step-by-Step Guide

Master calculating Watts, Kilowatts, VA, and Horsepower for DC and AC circuits with clear worked formulas and practical examples.

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7 min read

How to Calculate Voltage Drop: Step-by-Step Engineering Guide

Learn how to calculate cable voltage drop for long wire runs, apply NEC 3% and 5% rules, and select correct conductor sizes.

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8 min read

How to Size a Battery Bank for Solar, RV & Backup Power

Complete step-by-step sizing guide for calculating required battery capacity (Ah and Wh), Depth of Discharge, and temperature derating.

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6 min read

How to Size a Power Inverter for Off-Grid, RV & Backup Systems

Learn how to calculate continuous wattage, surge startup wattage, waveform selection (Pure Sine Wave vs. Modified), and DC cable sizing.

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9 min read

How to Size Electrical Wire Properly: NEC Ampacity & Voltage Drop

Complete practical guide to sizing copper and aluminum electrical wire using ampacity tables, temperature correction, conduit fill derating, and voltage drop formulas.

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8 min read

How to Calculate Three-Phase Motor Full-Load Amps (FLA) & Sizing

Step-by-step engineering guide to calculating three-phase induction motor full-load current, starting inrush, branch conductor sizing (125%), and overcurrent protection per NEC Article 430.

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7 min read

Transformer Sizing and Full-Load Current Calculation Guide

Learn how to calculate primary and secondary full-load amps for single-phase and three-phase transformers, determine required kVA capacity, and size overcurrent protection per NEC Article 450.

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9 min read

Solar Battery Bank Sizing Guide: Depth of Discharge & Peukert Derating

Comprehensive engineering sizing guide for off-grid and backup solar battery banks, incorporating daily Watt-hour audits, Depth of Discharge limits, temperature derating, and Peukert factor effects.

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8 min read

Conduit Fill Percentage and Jam Ratio Calculation Guide

Learn how to calculate conduit fill capacity per NEC Chapter 9 (Tables 1, 4, and 5), avoid cable jamming on multi-conductor pulls, and size pull boxes.

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7 min read

Wire Size for a 100 Amp Service: Copper, Aluminum and Distance

The exact conductors for a 100A residential service: 4 AWG copper or 2 AWG aluminum under NEC 310.12, plus grounding sizes and voltage-drop checks for long runs.

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6 min read

EV Charger Circuit Sizing: Breaker, Wire and Outlet Guide

How to size a home EV charging circuit the NEC way: charging is a continuous load at 125%, so a 48A charger needs a 60A circuit. Includes the NM-B trap that fails inspections.

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6 min read

Hot Tub Wiring: 50 Amp GFCI Circuit, Wire Size and NEC 680 Rules

Wire a 240V hot tub safely: 50A GFCI protection per NEC 680.44, 6 AWG copper conductors, an insulated equipment ground, and a disconnect within sight of the tub.

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