49 tools
Electricity
Ohm's law, single and three-phase power, voltage drop, cable sizing and electronics basics.
Tools in this category
- ElectricityOhm's Law CalculatorEnter any two of voltage, current and resistance and get the third, plus the power.
- ElectricityElectricity Cost CalculatorDaily, monthly and yearly running cost of any appliance from its wattage and hours of use.
- ElectricitySingle-Phase Power CalculatorActive, apparent and reactive power of a single-phase load from voltage, current and power factor.
- ElectricityVoltage Drop CalculatorVoltage drop in volts and percent along a copper cable, for single-phase and three-phase circuits.
- ElectricityThree-Phase Power CalculatorActive and apparent power of a balanced three-phase load, in watts, kW and kVA.
- ElectricityCable Cross-Section CalculatorMinimum conductor cross-section needed to keep voltage drop within a chosen limit.
- ElectricityMotor Full-Load Current CalculatorEstimate the full-load current of a three-phase motor from its shaft power, efficiency and power factor.
- ElectricityAWG to mm² ConverterConvert an American Wire Gauge number into conductor diameter and cross-sectional area.
- ElectricitySolar Panel Output CalculatorDaily and yearly production of a photovoltaic array, and the value of the electricity it replaces.
- ElectricitySeries and Parallel Resistor CalculatorEquivalent resistance of two resistors connected in series and in parallel.
- ElectricitykVA to Amps CalculatorCurrent drawn by a load rated in kVA, for single-phase and three-phase supplies.
- ElectricityRLC Impedance and Resonance CalculatorImpedance, phase angle, resonant frequency, Q factor and bandwidth for a series or parallel RLC circuit.
- ElectricityLED Series Resistor CalculatorResistor value and power needed to run an LED safely from a given supply.
- ElectricityBattery Life CalculatorEstimate how long a battery will last from its capacity and the current drawn.
- ElectricitySolar Battery Bank CalculatorBattery capacity in amp-hours for a daily consumption and a chosen number of cloudy days.
- ElectricityBattery Charging Time CalculatorHow long a battery takes to charge, with the charge rate expressed as a C-rate.
- ElectricityWire Resistance CalculatorResistance of a conductor from its length, cross-section and resistivity.
- ElectricityRMS CalculatorThe root mean square of a waveform or a list of readings, with peak, average, form factor and crest factor.
- ElectricityVoltage Divider CalculatorOutput voltage, current and power dissipation of a two-resistor divider.
- ElectricityInverter Size CalculatorInverter rating for a given load, with the DC current it will draw at full load and on surge.
- ElectricityGenerator Size CalculatorThe generator rating needed for a given running load plus the surge of the largest motor, in W and kVA.
- ElectricityLED Strip Power Supply CalculatorTotal wattage, current and recommended power supply size for a run of LED strip.
- ElectricityPower Factor Correction CalculatorCapacitor bank size in kvar needed to raise the power factor from one value to another.
- ElectricityRoom Lighting CalculatorTotal lumens and number of luminaires needed to reach a target illuminance.
- ElectricitySpeaker Impedance CalculatorThe load an amplifier sees from several drivers wired in series, in parallel or series-parallel, with the current and voltage.
- ElectricityAmplifier Power CalculatorHow many watts a speaker needs to reach a given loudness at a given distance, with the headroom counted in.
- ElectricityCable Power Loss CalculatorPower wasted as heat in a cable run, and what that waste costs over a year.
- ElectricityInductor Combination CalculatorTotal inductance of any number of coils in series or parallel, with the other arrangement shown alongside.
- ElectricityMotor Efficiency CalculatorEfficiency, losses and the yearly cost of those losses for a motor.
- ElectricityBattery Pack Configuration CalculatorVoltage, capacity and energy of a series-parallel pack, with the runtime and current at a given load.
- ElectricitySeries and Parallel Capacitor CalculatorEquivalent capacitance of two capacitors in parallel and in series.
- ElectricityPassive Crossover CalculatorCapacitor and inductor values for a first or second order passive crossover, from the crossover frequency and the driver impedances.
- ElectricityAudio Level ConverterConvert between dBu, dBV, volts and dBFS, with the alignment level you choose, plus peak and peak-to-peak voltage.
- ElectricityLumens to Watts CalculatorLuminous efficacy of a lamp, the incandescent equivalent and the yearly running cost.
- ElectricityPV String Sizing CalculatorMaximum modules per string from the cold open-circuit voltage, with the minimum for the MPPT window.
- ElectricityInductive and Capacitive Reactance CalculatorReactance of a coil and a capacitor at a given frequency, plus the resonant frequency of the pair.
- ElectricityCable Ampacity Derating CalculatorCorrected current-carrying capacity of a cable, and the table value a design current needs.
- ElectricityAudio Headroom CalculatorHeadroom, crest factor, the noise floor of a given bit depth and how much of the available range a recording actually uses.
- ElectricityTransformer Turns Ratio CalculatorVoltage ratio and secondary turns of a transformer from the primary and secondary voltages.
- ElectricityCapacitor Energy CalculatorEnergy stored in a capacitor and the charge it holds, from capacitance and voltage.
- ElectricityRC Time Constant and Filter CalculatorTime constant, settling time and cut-off frequency of a resistor-capacitor pair.
- ElectricityThree-Phase Fault Current CalculatorProspective short-circuit current at a transformer's terminals, with the peak current and the fault level.
- ElectricityOp-Amp Gain CalculatorGain of an op-amp stage in both configurations, in ratio and decibels, with the output and the bandwidth left.
- ElectricityAntenna Length CalculatorQuarter-wave, half-wave and full-wave lengths for a frequency, with the dipole half-length.
- ElectricityCable Short-Circuit Withstand CalculatorMinimum cable cross-section for a fault current and clearing time, and how long a given cable survives it.
- ElectricitySolar Panel Payback CalculatorSee how long a solar system takes to pay for itself, with your own tariffs and panel degradation.
- ElectricityStar-Delta (Y-Δ) Conversion CalculatorEquivalent star resistances from three delta resistances, and back again.
- ElectricityWheatstone Bridge CalculatorBridge output voltage, the resistance that would balance it, and the sensitivity in millivolts per ohm.
- ElectricityUPS and Battery Backup Runtime CalculatorWork out how long a battery bank will carry a given load through a power cut.