[Richard]

I believe the cooktop is intended for international markets where the standard is 208. So, the US convention of black for one leg, red for the second leg, and white for neutral does not apply to their drawing. The international standard will have you wiring black to one hot leg and white to the second.

There is a wiring diagram on the amazon site for this cooktop that shows exactly this situation. It confirms the way that you wired it. https://www.amazon.com/Induction-Electri...B0861FY7LL