IEC 60301:2012 gives a series of preferred diameters of the finished wire terminations of capacitors and resistors for use in electronic equipment. This third edition cancels and replaces the second edition, published in 1971, and its Amendment 1, publish
DS/EN 60301:2012 history
2012DS/EN 60301:2012 Preferred diameters of wire terminations of capacitors and resistors