Electrical calculations, worked through
Voltage drop, conductor sizing, conduit and box fill, load, power factor and DC circuits. Every tool shows the formula, the code reference and the working behind the answer.
More electrical tools
Battery Runtime Calculator
Realistic runtime with depth of discharge and Peukert correction.
Open →Box Fill Calculator
Volume allowances per Article 314, with a pass or fail.
Open →Conduit Fill Calculator
Fill percentage against the Chapter 9 limits, EMT and PVC.
Open →kVA Calculator
kVA, kW, amps and power factor in any direction.
Open →Ohm's Law Calculator
Any two values in, the other two out, with the steps.
Open →Power Factor Calculator
kVAr required to reach a target power factor, plus current saved.
Open →Resistor Colour Code Calculator
Decode 4, 5 or 6 band resistors, or find bands for a value.
Open →Transformer Size Calculator
Standard kVA from your load, plus primary and secondary FLA.
Open →Voltage Drop Calculator
Volts lost, percent drop and the length limit for any conductor size.
Open →Wire Size Calculator
Sizes for ampacity and voltage drop, plus the breaker to match.
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