The electrical bench
toolbox.
Size wire, estimate voltage drop, work out three-phase power and check the basics of circuits.
Keep this toolbox for offline use
14 useful places to start.
Resistive estimates for low-voltage work. Allowable current depends on insulation and installation, so follow your local wiring rules and use a qualified electrician for installations.
AWG wire gauge calculator
Look up the diameter, area and resistance of an American Wire Gauge size, or find the AWG for a wire diameter.
Voltage drop calculator
Find the voltage drop, percentage and power lost in a cable run of copper or aluminium.
Three-phase power calculator
Work out kW, kVA and kVAr for a three-phase load, and the capacitor needed to improve its power factor.
Ohm’s law calculator
Calculate current and resistor power from voltage and resistance.
DC electrical power calculator
Relate voltage and current to power and energy over time.
Series & parallel resistors
Calculate ideal resistance in series or parallel.
Loaded voltage divider
Calculate a resistor divider with an optional load across its lower resistor.
Resistor colour code reader
Decode four- or five-band resistor values and tolerance limits.
LED series resistor calculator
Estimate the ideal resistor and dissipation for a low-voltage DC LED string.
Wire resistance & temperature
Calculate conductor resistance and apply a supplied linear temperature coefficient.
Appliance electricity cost
Estimate energy and cost from power, usage and your tariff.
Battery energy runtime
Estimate constant-load runtime after supplied usable-depth and efficiency factors.
Electrical resistance converter
Translate ohms, milliohms, microohms, kilohms and megohms.
Power converter
Convert power units with clearly labelled standards.
A few things you
can tick off.
- Find the voltage drop of a long cable run
- Pick an AWG size for a diameter
- Correct the power factor of a motor