3bm » Electronics

This calculator uses rule of thumb data which will be more than accurate enough in most cases. It must however, be used with intelligence.

Naturally, I cannot be held liable for any damage or loss as a consequence of its use or misuse.

Calculations are for an un-insulated solid copper wire in free air at 25°C.

Parameters marked with a * are required. Others are optional.

Wire diameter	thou mm	*Enter the wire diameter in your preferred units
Wire length	inch mm	Used to calculate resistance, voltage drop and power
Operating current	A	DC or RMS operating current - used to calculate voltage drop and power (<30A)
Frequency	kHz	Signal frequency - leave at 0 for DC

Cross sectional area	sq. thou sq. mm	Cross sectional area of the wire
Ampacity	A	Current carrying capacity at DC
Fusing current	A	Fusing current at DC
Skin depth	thou µm	Skin depth at selected frequency - assumes copper wire
Skin ratio	%	Percentage of cross sectional area used at selected frequency
Resistance	ohms	Resistance of wire at selected frequency
Voltage drop	mV	Voltage drop along wire at selected frequency
Power dissipated	W	Power dissipated in wire at selected frequency