TO be in line with code rules, fixed 220 volt wiring should use black and red hot wires from the breaker box, like this:
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White conductor, when used for live voltage, can be tolerated if covered with black or red plastic tape at both ends to signal any third party that it is not at ground voltage. I understand you are using flexible wiring though that is not available in red/black combinaison.
For feeding voltage, it makes no difference, of course.