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Electrical, HVAC & Mechanical

Calculators and technical references for mechanical systems, electrical wiring layouts, and thermal building loads. Sized to meet National Electrical Code (NEC) and ASHRAE guidelines.

Interactive Calculators

⚡ Voltage Drop Calculator

Calculate electrical voltage drop and wire sizing. Estimates circuit safety limits using NEC copper/aluminum resistance.

Custom Sizing Variants: Copper Aluminum By Awg

🔌 Wire Ampacity Sizer

Determine maximum allowable current carrying capacity (ampacity) and AWG/metric sizes under electrical codes.

🔥 BTU / HVAC Calculator

Calculate room BTU heating/cooling loads and HVAC tons. Evaluates insulation and solar exposure parameters.

Custom Sizing Variants: Cooling Heating By Room

🧪 Pipe Volume Calculator

Calculate piping cylinder volumes, internal capacities, and filled water weights for fluid systems.

⚙️ Gear Ratio Calculator

Calculate gear ratio, speed reductions, output RPM, and torque multipliers. Includes standard AGMA tooth calculations.

Custom Sizing Variants: To Speed With Tire Size Rpm Rear End

Reference Tables

Trade Glossary Terms

Cooling Load Voltage Drop