For field electricians
Electrical field tools
Quick calculations and references for residential, commercial, and industrial work.
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Electrical work
Electrical CalculationsSolve electrical quantities and check circuit performance with field-focused calculations.Conductors & RacewayCheck conductor, grounding, raceway, box, and wiring installation tasks.Loads & ServicesPlan service loads, feeders, jobsite power, and connected energy systems.Equipment & SystemsWork with motors, communications, protection, and installed electrical equipment.
Field tools
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Voltage Drop and Wire Size CalculatorEstimate voltage loss and compare conductor sizes.Low-Voltage Cable Voltage Drop EstimatorEstimate DC control-cable drop from cable data-sheet resistance.PoE Power Budget EstimatorCompare device demand with switch and port power limits.Temporary Power Cord Screening ToolCheck cord current and voltage drop from jobsite inputs.Feeder Conductor Sizing and Voltage Drop CalculatorCompare feeder ampacity and voltage drop.Conduit Fill CalculatorCheck raceway fill.Raceway Fill and Ampacity CalculatorCheck mixed raceway fill and conductor ampacity adjustments.Conduit Bend CalculatorLay out stub-ups, offsets, and saddle bends.Box Fill CalculatorCheck box volume allowances.Pull Box and Junction Box Sizing CalculatorSize pull boxes for large-conductor raceway entries.Cable Pull Tension and Sidewall Pressure CalculatorEstimate tension and bend pressure along a cable-pull route.Motor Full-Load Current and Circuit Protection ReferenceLook up motor current, conductor ampacity, and protection limits.Industrial Enclosure Environment ReferenceFilter NEMA type descriptions by location and exposure.Energy Control Checklist BuilderRecord energy sources and isolation points against a written procedure.Arc-Flash Label Data HelperCheck that study-supplied label fields and review records are present.Three-Phase Motor Power and Torque CalculatorEstimate motor input power, shaft horsepower, and torque.VFD and Motor Compatibility WorksheetScreen rated current and track manufacturer review items.Motor Voltage Drop EstimatorEstimate running and starting voltage drop from motor and conductor data.Motor Overload Protection Setting ReferenceCalculate normal and conditional overload trip-current limits.Available Fault Current and SCCR ScreenEstimate bolted-fault current and compare device and assembly ratings.Ohm’s Law and Power CalculatorSolve circuit values and convert AC current, kW, kVA, and kvar.Conductor Ampacity CalculatorApply conductor ampacity corrections.Branch Circuit Conductor and Breaker CheckCompare load, conductor ampacity, and breaker rating.Equipment Grounding Conductor CalculatorLook up minimum EGC size.Grounding Electrode Conductor Size CalculatorLook up a grounding electrode conductor size.Bonding Jumper Sizing ReferenceLook up main, system, and supply-side bonding jumper size.Cable Tray Fill and Ampacity WorksheetCompare cable area and apply an entered ampacity factor.Standard Overcurrent Device Rating CalculatorFind the next standard fuse or breaker rating.GFCI and AFCI Requirement FinderCheck selected circuit-protection requirements.Dwelling Load CalculatorCalculate one-family service load.Commercial Feeder and Service Load CalculatorEstimate non-dwelling service or feeder load.Commercial Material and Labor EstimateBuild a rough estimate from quantities and user-entered prices.Dwelling Receptacle and Circuit Quick ReferenceReview outlet placement and required circuits by room.Receptacle and Plug Identification ReferenceLook up common NEMA markings and ratings.NM Cable Support and Protection ReferenceCheck cable support, framing protection, and floor passages.Existing Service Capacity CalculatorCheck proposed loads against an existing service.EVSE Circuit and Service Load PlannerCheck one charger circuit and its added service load.EV Charging Time CalculatorEstimate time to charge an EV battery.Transformer Current and Overcurrent Protection CalculatorCalculate winding current and review primary/secondary device limits.Control Transformer Load CalculatorCompare continuous and startup control VA with transformer capacity.Electrical Unit ConverterConvert electrical values and conductor area.Lighting Fixture Count and Spacing EstimatorEstimate fixture count and even-row layout spacing.Residential Material Takeoff EstimatorEstimate device, box, cable, raceway, and conductor quantities.Battery Runtime CalculatorEstimate battery runtime and average DC current.Fire Alarm Battery Load WorksheetCalculate standby and alarm amp-hour demand from project inputs.Emergency Lighting Runtime ScreenCheck emergency lighting energy against a required duration.Generator Load and Motor Start EstimatorCompare steady and motor-start generator demand.PV String and DC Wiring CalculatorEstimate cold string voltage and DC conductor drop.