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.
Lighting Circuit Voltage Drop Calculator
Estimate lighting-circuit voltage drop, percent drop, end voltage, and approximate conductor loss from entered electrical values.
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Light Loss Factor Calculator
Estimate maintained lumens by multiplying initial lumens by the project-selected light-loss factors.
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LED Series Resistor Calculator (DC Supply to Resistor Value)
Estimate the current-limiting resistor for a series LED string and show a rounded-up common-value candidate.
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LED Retrofit Payback Calculator
Estimate annual energy savings and simple payback from fixture wattage, count, operating schedule, electricity rate, and project cost.
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Leakage Current Screen Calculator
Compare entered leakage current with a documented reference and express it as a share of entered load current without embedding a safety limit.
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Inverter Efficiency Calculator
Estimate inverter efficiency, loss power, and loss percent from matching DC input and AC output power values.
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Insulation Test Voltage Calculator
Compare entered insulation test voltage with equipment rating and a documented procedure window without selecting the required test voltage.
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Insulation Test Trend Calculator
Estimate insulation resistance ratio, change, and percent change from start and end readings over an entered interval.
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Insulation Test Duration Calculator
Estimate test completion, remaining time, and planned readings from entered duration and reading-interval values.
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Instrument Transformer Burden Calculator
Estimate burden voltage and apparent burden from an entered transformer secondary current and resistive burden.
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Industrial Feeder Capacity Calculator
Estimate adjusted feeder load, current, utilization, and remaining capacity from an entered rating and demand factor.
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Industrial Demand Load Calculator
Estimate coincident industrial demand from entered load blocks and reviewed process demand factors.
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Industrial Branch Load Calculator
Estimate adjusted branch VA and line current from explicit load, demand, continuous, voltage, and phase inputs.
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Impedance Magnitude Calculator
Estimate single-frequency AC impedance magnitude, phase angle, and power-factor magnitude from resistance and net reactance.
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Grounding Electrode Conductor Size Calculator
Compare selected conductor area with an entered grounding value while keeping the result separate from standards-table interpretation.
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Grounding Conductor Continuity Calculator
Estimate corrected grounding-conductor resistance and compare it with an entered reference threshold.
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Grounding Bond Test Calculator
Estimate loop and corrected bond resistance from a grounding or bonding voltage-drop test and compare the result with an entered reference.
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Ground Rod Spacing Calculator
Compare entered grounding-electrode spacing with rod length and an entered target without making a grounding design decision.
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Ground Grid Resistance Calculator
Estimate simplified ground-grid resistance from soil resistivity, grid area, and parallel paths for preliminary review.
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Ground Fault Current Calculator
Estimate prospective and factored ground-fault current from entered voltage, impedance, and screening factor for preliminary review.
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GFCI Trip Time Calculator
Compare measured GFCI trip time with an entered reference limit and recorded test current.
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Generator Transfer Load Calculator
Estimate transfer load, usable generator capacity, reserve margin, and utilization from entered ratings and load assumptions.
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Generator Backfeed Safety Calculator
Organize transfer and source-control records for qualified review without making a field or energization conclusion.
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Fuse Size Calculator
Estimate an entered fuse reference and compare it with a selected fuse rating for qualified review.
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