Conduit Bending
Saddle bends, offsets, kicks, segment bends, rolling offsets, and conduit bend multipliers for field layout.
Electrical Calculators for Motors, Solar, Voltage Drop, and Loads
Find calculators for motors, conduit bends, wire sizing, voltage drop, lighting, solar, backup power, and test readings.
Calculator Categories
Browse calculation families by equipment, field task, and electrical method.
Electrical Formulas
Voltage, current, resistance, power, energy, power factor, and cost calculators for basic electrical math.
Estimating And Material Planning
Material takeoff, conduit cut length, wire pull length, waste allowance, and job quantity calculators.
Lighting And Illumination
Lumens, footcandles, lux, fixture count, lighting load, emergency lighting, and lighting energy calculators.
Load Calculations
Residential, commercial, industrial, feeder, panel, service, appliance, HVAC, and EV load calculators.
Motors And Power Quality
Motor current, starter sizing, VFD checks, transformer kVA, generator load, harmonics, and power quality.
Solar And Backup Power
Battery capacity, runtime, inverter size, UPS capacity, generator load, fuel use, and backup power planning.
Solar And PV Systems
PV array size, solar panel count, string voltage, cable voltage drop, charge controller checks, and solar energy output.
Testing, Protection And Grounding
Insulation resistance, short-circuit current, pull-box sizing, grounding, bonding, touch voltage, and protection checks.
Wire, Cable And Raceway
Wire size, cable resistance, raceway fill, ampacity, voltage drop, bend radius, and pull-length calculators.
Available Calculators
Open a calculator to enter values, inspect the formula, and read the result units.
Rolling Offset Calculator
Finds the true rolling offset, bend travel, mark locations, and estimated shrink from horizontal and vertical displacement, bend angle, and a reference mark.
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RLC Resonance Calculator
Estimates ideal resonant frequency and first-order series-RLC quality metrics from inductance, capacitance, and series resistance.
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Receptacle Load Calculator
Estimates connected and demand receptacle load in VA, then converts the demand load to circuit current from the entered voltage and phase model.
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RC Time Constant Calculator (tau and 63.2%)
Estimate the ideal first-order RC time constant and exponential target time from resistance, capacitance, transition mode, and target percentage.
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Power Factor Correction Calculator
Estimates required correction kVAR and apparent-current reduction from kW, current power factor, target power factor, voltage, and phase.
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Parallel Conductor Calculator
Compares ideal and highest-loaded current per parallel conductor set with entered ampacity using total load, set count, and mismatch allowance.
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Panel Schedule Calculator
Totals panel schedule rows, phase distribution, maximum phase current, rating margin, and remaining spaces from entered circuit data.
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Neutral Load Calculator
Estimates neutral current and phase-current imbalance for split-phase three-wire or linear three-phase wye models.
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NEMA Code Letter Calculator
Estimates kVA per horsepower and the matching NEMA-style code-letter range from horsepower, voltage, phase, and locked-rotor current.
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Motor Voltage Drop Calculator
Estimates running and starting voltage drop and remaining motor voltage from current, one-way length, conductor resistance, system voltage, and phase model.
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Motor Torque Calculator (hp or kW to lb-ft and N-m)
Convert motor horsepower or kilowatts and rpm into shaft torque in lb-ft and N-m.
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Motor Slip Calculator
Estimates induction-motor slip as a speed difference in rpm and as a percentage of synchronous speed from measured rotor speed.
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Motor Overload Calculator
Compares a motor overload setting from nameplate FLA and an entered percentage with a recorded device setting, with motor load shown in kVA.
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Motor Efficiency Calculator
Estimates ideal motor efficiency and power loss from electrical input power and mechanical output power.
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Motor Disconnect Size Calculator
Compares a motor disconnect current basis with an entered disconnect rating using motor FLA, multiplier, voltage, and phase.
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Lumen Calculator
Estimates required lumens, target lux, and an initial fixture count from room area, target illuminance, coefficient of utilization, light loss factor, and fixture lumens.
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Locked Rotor Current Calculator
Estimates motor locked-rotor current from full-load current and a selected multiplier, with an optional comparison against a starting-current reference.
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Lighting Load Calculator
Estimates connected and adjusted lighting VA and current from area, project load-density basis, demand factor, continuous-load factor, voltage, and phase.
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Lighting Layout Calculator
Estimates an initial fixture grid and nominal average illuminance from room dimensions, mounting height, spacing criterion, and fixture lumens.
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Lighting Energy Savings Calculator
Estimates annual energy use, electricity-cost savings, and simple payback for a lighting retrofit from fixture wattage, operating schedule, electricity rate, and project cost.
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Lighting Circuit Load Calculator
Estimates lighting branch-circuit load, current, and fixture capacity from fixture wattage, quantity, continuous-load factor, voltage, phase, and an entered breaker value.
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LED Resistor Calculator
Estimates the ideal current-limiting resistor for a series LED string and shows a rounded-up common-value candidate for component review.
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LED Driver Load Calculator
Estimates LED-driver watts, VA, adjusted continuous load, and circuit current from driver rating, quantity, power factor, multiplier, voltage, and phase.
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Inverter Size Calculator
Estimates preliminary inverter capacity from running load, surge load, power factor, planning margin, and efficiency. It does not select a model or approve installation details.
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