Electrical Engineering
Electrical engineering calculators for transformers, motors, power factor, arc flash, solar arrays, and NEC code compliance.
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Transformer Sizing Calculator
Size single-phase and three-phase transformers: calculate required KVA, full load current, and select next standard size.
Motor Starting Current Calculator
Calculate motor full load amps, starting inrush current, voltage drop during starting, and starting KVA demand.
Power Factor Correction Calculator
Calculate the capacitor bank size (KVAR) needed to improve power factor and estimate energy cost savings.
Short Circuit Current Calculator
Calculate available fault current, X/R ratio, and interrupting duty at a point downstream of a transformer.
Cable Ampacity Calculator
Determine cable ampacity with NEC derating factors for temperature, conduit fill, and continuous loads.
Harmonic Distortion Calculator
Calculate Total Harmonic Distortion (THD) and check compliance with IEEE 519 harmonic limits.
Grounding System Calculator
Design grounding electrode systems: calculate single rod resistance, parallel rod resistance, touch and step voltages.
Lighting Design Calculator
Calculate the number of light fixtures needed using the lumen method: N = (E × A) / (F × UF × MF).
Emergency Generator Calculator
Size emergency generators with altitude and temperature derating, fuel consumption, and runtime estimates.
Solar Panel Array Calculator
Size a solar panel array: calculate panel count, array capacity, daily/annual production, and required roof area.
Battery Bank Sizing Calculator
Size a battery bank: calculate series/parallel configuration, total batteries, and usable capacity for off-grid and backup systems.
Arc Flash Calculator
Estimate arc flash incident energy, flash boundary, PPE category, and required cal rating per IEEE 1584.
Conduit Fill Calculator
Check NEC conduit fill compliance: calculate fill percentage, compare to code limits, and find maximum conductor count.
Voltage Regulation Calculator
Calculate voltage drop, drop percentage, and receiving-end voltage for power cables with resistance and reactance.
Demand Load Calculator
Calculate residential service demand load per NEC Article 220: general lighting, appliances, HVAC, and service size.