Guide Topics
Electrical Guides
Engineering Guide Library
AWG Wire Size Chart & Reference Guide
Diameter, area, resistance and ampacity by AWG size
NEC Table 310.16
Copper and aluminum ampacity at 60, 75 and 90 °C
Wire Size for 200 Amp Service
Table 310.12 conductor sizes for a 200 A dwelling service
100 Amp Wire Size Guide
Table 310.12 conductor sizes for a 100 A dwelling service
EV Charger Wire Size Guide
Wire size for Level 2 charger circuits
Electrical Power Calculations
Master the fundamentals of electrical power, current, voltage, and energy calculations.
Topics Covered:
- Watts, Amps, Volts Relationships
- Power Factor Analysis
- Single & Three Phase Systems
- Ohm's Law Applications
Related Calculators:
NEC Code Compliance Guide
Navigate the National Electrical Code requirements for safe electrical installations with detailed code references.
Topics Covered:
- Circuit Protection Requirements
- Grounding Systems
Related Calculators:
Power Factor Explained
Understanding reactive power, apparent power, and power factor correction for efficient electrical systems.
Topics Covered:
- Real vs Apparent Power
- Inductive & Capacitive Loads
- Power Factor Correction
- Energy Efficiency
Related Calculators:
Single vs Three Phase Systems
Compare electrical distribution systems, their applications, and advantages in residential and commercial settings.
Topics Covered:
- Voltage System Configurations
- Load Distribution Methods
- Motor Applications
- Power Transmission Efficiency
Related Calculators:
Frequently Asked Questions About These Guides
Which NEC edition do these guides reference?
The guides cite the 2023 NEC unless a page names another edition. The 2026 NEC was issued by NFPA on August 20, 2025 and took effect September 9, 2025.
Are these guides authoritative for code-compliance work?
These guides are educational references. The authoritative source is the NEC document published by NFPA, available at nfpa.org. Local jurisdictions may adopt the current NEC edition with amendments (state-specific articles), or remain on an older edition. Always confirm with your local Authority Having Jurisdiction (AHJ) before installing.
How are these guides different from each other?
The NEC Table 310.16 page is the canonical ampacity reference. The AWG wire size chart is the physical-properties reference (diameter, area, resistance). The per-amperage guides (100 A, 200 A, EV charger) are installation-specific. Power Calculations, Single-vs-Three-Phase, and Power Factor are theory references that support the practical guides.