Calculators
Transformer Sizing Chart — kVA to Full-Load Amps
Transformer full-load amps from kVA at common voltages — three-phase and single-phase primary and secondary currents for dry-type planning. Includes...
Electrical
Calculators
Calculators
Three-Phase Power Chart — Line Current, Wye/Delta & kVA
Three-phase-only reference: line vs phase relationships (Wye/Delta), kW→amps at common industrial voltages including motor PF 0.85, and kVA ↔ amp...
Calculators
Short Circuit Current Chart — Transformer Isc Estimates
Approximate transformer secondary available fault current from kVA and %Z — infinite-bus estimate for AIC planning (not a full study)....
Calculators
Sub-Panel Sizing Guide — Garage & Shop Feeder Panels
A sub-panel is a feeder panel — not a second service. Size the feeder demand and conductors first, then pick...
Calculators
Commercial Load Calculation Guide — NEC Article 220 Part III
Commercial service and feeder demand follows NEC Article 220 Part III — occupancy lighting unit loads, receptacle VA, equipment demand...
Electrical
Electrical / NEC Basics Practice Quiz
Free electrical practice quiz on voltage drop notes, ampacity derating concepts, box fill counting, GFCI/AFCI types, and grounding vs bonding....
Calculators
Arc Flash PPE Category Chart — NFPA 70E Category Overview
NFPA 70E PPE category overview for education: typical incident-energy ranges and clothing layers. Always follow the current standard, equipment labels,...
Calculators
OSHA Noise Exposure Chart — Permissible Duration by dBA
OSHA Table G-16 style reference: when sound level goes up, allowed exposure time comes down. Use this chart for quick...
Calculators
kW, kVA & Amps Chart — Conversion Tables at 120–480V
Quick conversion tables for amps from kW and kVA at common system voltages — single-phase and three-phase — at power...
Calculators
Extension Cord Gauge Chart — AWG, Ampacity & Max Length for 120V/240V
Pick cord gauge from ampacity first, then check length so voltage drop stays under control. These tables give recommended maximum...